This is what happens when people are ignorant of history and social customs.
Firstly, the Prophet's marriage to Aisha (ra) was a revelation from Allah, Aisha was shown to the Prophet twice in his dreams, a man was carrying her on silken cloth and said to the Prophet, 'This is your wife.' The Prophet said, 'If this dream is from Allah, He will cause it to come true.' In all pre-modern traditional cultures, it was not abnormal for girls to consummate marriages between the ages of 10 and 12 and that was perfectly acceptable back then. Muhammad's (ﷺ) worst enemies would slander him with the worst accusations imaginable, they called him a "magician", a "sorcerer", a "mad man", but they never slandered him because he married Aisha at a young age since was the norm of their time. Neither the Jews or the Christians of his time found any issue with the Prophet Muhammad's (ﷺ) marriage to Aisha. Today we find that shocking, but the pre-modern people lived in a very different time period. In the history of the world, there’s never been a universally agreed upon minimum age for marriage. Every religion, civilization, history, and country has its own minimums. So what’s the perfect age for marriage? Depends on who you ask! Some say minimum age of marriage should be 18 for both boys and girls. Some say 16, and some even say 14 or 12. The age of marriage, throughout history, before the 19th century was very low. Some cultures, including Britain, allowed girls as young as 7 to be married legally (see "William Blackstone's Commentaries on the English Law" published 1867, page. 110). Most of Africa, Asia, Europe and the rest of the world married off their children as soon as they reached the age of puberty. Please see the following link:
Age of Consent in European & American History – Discover The Truth (discover-the-truth.com)
When does a child reach the age of puberty? See the following link:
Stages of puberty: what happens to boys and girls - NHS (www.nhs.uk)
As you can see in the NHS link above that a child can reach puberty (adulthood) between the age of 8 to 14. So, historically speaking, in pre-modern societies as soon as children showed signs of adulthood they were married. Modern standards of liberal/secular "morality/ethics" can not be applied on pre-modern societies. That would render every single human a pedophile. Some cultures in Africa and Asia follow the old system to this day. If we judged all humans (who lived before the 19th century) by our standards today then that would render all of them morally redundant. Applying modern standards to pre-modern societies is called anachronism (see link):
ANACHRONISM | meaning in the Cambridge English Dictionary
In conclusion, those who condemn Muhammad (ﷺ), a man alive in the 7th century Arabia, for doing something normal (i.e. getting married to an adult), even by the standards of the 19th century are in fact guilty of condemning the rest of humanity for doing the same thing.
Finally, there can only be two reasons for people to "criticize" the Prophet Muhammad (ﷺ) for this:
1. Ignorance of human history or 2. Blind irrational hatred. Most Islamophobias have both these qualities. They are both ignorant and blind haters. Do the Muslims today have to get married that young? The answer is no. Times have changed, thinking has changed, people have changed. Most Muslims do not get their children married that young because they live in different times. Besides, it has become illegal in most countries to do so and Muslims are mostly law abiding citizens. It is not a religious obligation in Islam to get married as soon as one hits the age of puberty. The main condition of marriage being consummated in Islam is physical maturity and even that is contingent upon the legal systems of the countries they reside in, also Islam teaches that there should be no harm in such a marriage whether it's physical or mental. Did the Prophet do anything wrong by marrying Aisha (may Allah be pleased with her)? Absolutely not, as he did what the rest of humanity considered normal practice in that day and age.
All Islam-haters or Islamophobes must be ready to either condemn their ancestors as pedophiles or be ready to remain silent on this matter. They should get a life, this charge is not working. Most Orientalists or western scholars (such as Ockley, Gibbon, Noldeke, Goldziher and Muir), who wrote on the Prophet Mohammad (peace be upon him) before the 20th century, did not criticize him on this matter. They found other reasons to attack the Prophet but NEVER did they use the age of Aisha as a point of contention. This was due to their own indulgence in the same practice i.e. marrying their daughters off young. Pre-modern societies did not see marrying off their daughters young as pedophilia. They divided children and adults by determining the age of puberty. To them, anyone who had reached the age of puberty was not a child anymore:
Child | Definition of Child by Oxford Dictionary on Lexico.com also meaning of Child
Lastly, Aisha was very happy with the marriage and loved her husband greatly and would always defend him, if she didn't find anything wrong with the marriage then I guess it's better if you shut up and get a life. Aisha is the most influential women in Muslim history. She has a high status in Islam. She was an intelligent women with a great memory. She memorized the Quran, she knew medicine, poetry and Islamic matters. When the companions of the Prophet didn't know an Islamic ruling on an Issue, they would always ask Aisha for the ruling and she always knew it. She was the top primary narrator of Hadith. She loved her husband and would always defend him. Her relationship with the Prophet was a beautiful one.
Where's the reference that the Prophet (ﷺ) use to thigh Aisha (May Allah be pleased with her) before the age of 9? Show me a Sahih Hadith that states that, if you don't then you're a liar. That Hadith that you just posted only states that she cleaned the Prophet's clothes, it doesn't mention how old she is and it doesn't mention anything about "thighing", and Aisha didn't live with live with the Prophet until 9 so you're just making shit up.