There's this guy I usually have on in the background on youtube who replicates chemistry experiments -- or attempts to. It's pretty rare to see him find a paper that doesn't exaggerate yields or go into enough details, and he has to guess things.
I did a lot of chemistry for a year when I worked as a QA for a pharmaceuticals company before going to uni.
So much so that when I did Chemistry at uni I got asked if I was cheating a few times in labs, until I explained.
It's actually really hard to get any experiment perfect the first time.
Even with a year's practice of measuring and mixing and titration and all the other skills you need, I'd still get low yields, or bad results occasionally. Better than everyone else, but still not perfect.
I also noticed that the more you do a particular process, the better results you will get. Just like practicing a solo on an instrument lots, or a particular pool shot, or cooking a particular meal. There's a level of learning and experience needed for each process, not all chemistry in general.
Was it perhaps "that chemist"? He has some decent videos on complete bogus papers but I don't think he does reproductions, I'd be interested in that channel if you happen to find it in your watch history.
You don't exaggerate yields, you just publish the best one you get out of a dozen attempts. Chemistry is messy.