This right here is the correct answer.

It's also why studies on the topic is really hard.

People aren't deliberately lying, but subconsciously ignoring what you actually eat is REALLY pervasive in people, and like you say, logging what you eat changes what you eat, in almost everyone.

So many people (including myself) that say "I just started lifting weights" did so much more. In reality what happens is you have an epiphany/catharsis/turning point in your life that makes you want to become healthy, and the direct action you make is start excercising, but the indirect actions you make are not stuffing your face with a bag of chips as often, and drinking more water, redistributing macros on your plate, and maybe substitute a protein shake for a meal at times.

And presto: You've lost a ton of weight (figuratively) "just by excercising a bit".

maybe not the complete truth but: drinking more water makes you feel fuller and thus less hungry, decreasing your overall calorie intake by making you less likely to snack.

Here's a study of just the satiety part [0]. Now, I won't state that there couldn't be an effect on diet anyway.

[0] "Drinking water prior to a meal does not affect hunger and satiety ratings in young adults and older subjects"

https://www.cambridge.org/core/services/aop-cambridge-core/c...

Even drinking more water alone might have been enough, it could have displaced you from consuming other beverages, like my own vice of sugary fizzy caffeinated drinks.