Reddit has an elaborate critique of Adnan Rashid's "Historical Analysis". https://www.reddit.com/user/RepliesAndAnswers/comments/ijbx68/age_of_aishah_historical_analysis_adnan_rashid/
1. Adnan Rashid ignores all standard schools of thought about Malthusian demography and known experts from the Cambridge group and others.
The standard schools of thought on demographics can be summarised as per "How the West 'Invented' Fertility Restriction" Nico Voigtländer & Hans-Joachim Voth 2011, https://www.nber.org/papers/w17314 which has in its abstract: "Europeans restricted their fertility long before the Demographic Transition. By raising the marriage age of women and ensuring that a substantial proportion remained celibate, the "European Marriage Pattern" (EMP) reduced childbirths by up to one third between the 14th and 18th century."
Known historical fact: Europeans married late. Adnan does not mention this and does not explain why he chooses to come to completely opposite conclusions.
2. Adnan Rashid ignores standard government statistics and known standard works about history.
Adnan uses Rifkin (a non historian) to claim that adolescence did not exist before 1900. And that girls married young, very young. He supports this with legal ages supposedly having been set very low and those ages supposedly being common or 'the norm'.
UK Historians in the Cambridge group looked into accusations by communists that people used to marry very young and built substantial evidence to the contrary.
Let us look at government reports first;
The Engish government reported on the Marriages in the country (which after 1836 also included Quackers, Jews etc. which had previously not been accepted as 'true' marriages since they were not Church of England.) .
https://archive.org/details/annualreportofre171854grea/page/n15/mode/2up Annual report of the Registrar-General of births, deaths and marriages in England. General Register Office. Government publishing marriage-statistics. look at the table at the bottom right:
1845: 119.539 newly-weds, , and 11.835 widowers/spinsters=131.374 first marriages for women.
Underage (i.e. requiring permission from parents because under 21: 19.376 14.75% were under 21 ).
The pattern is comparable for the rest of the columns with some variation per year.
Conclusion: About 85% of girls were 21 or older at first Marriage. Only 15% was 20 or younger.
"Marriages of minors.-9210 men and 28,797 women, or 38,007 men and women, married under 21 years of age ; so that the proportion of minors in 100 men who married was 5.77, in 100 women 18.03;"
So, age of first marriage saw 85% being 21 or over. 'minors' were registered separately and needed parental permission. It may not have been clalled adolescence: but onset of menstruation was certainly not the criterion.
Laslett, Peter The World We Have Lost (1965) most common marriage age in the records was 22 with an average of 24. "We have examined a thousand licences containing the ages of the applicants, issued by the diocese of Canterbury between 1619 and 1660 to people marrying for the first time. One woman gave her age as 13, four as 15, twelve as 16: all the rest were
17 and over, and 966 of the women got married for the first time after the age of 19, that is nearly 85 per cent. The commonest age of first marriage for women in this sample was 22, and the median age -- the age below which as many got married as got married above it - was about 22.75: the average, mean age was about 24.
Adnan Rashid is not aware of the most elementary historical approaches and evidence, or simply ignores it.