Would we react the same way if Lily or Kanak posted a similar video to help club/hobby level players get better?
I don't think they will claim that a retired player from 2 decades ago, will have the same or higher level today due to the game being evolved. If they do, I will still challenge it and want to see how is that possible. If you dare to state that, then need to explain it when challenged.
I have a 2. Bundesliga player in Germany right now - way higher level than a couple of table tennis Olympians in Paris, or Tokyo that I know. He has some hip injury and I told him to take 1 week break, because he has no league matches last week.
He said, last time he rested for 1 month, he had no feeling at all and took a long time to "catch up". So I told him to practice 1 session a day, and take the work load lighter, arranging physios and what not.
Of course if he was to play a hobby player with no feeling due to the long rest, then I'm sure even with playing with a phone or pot, he will win. But at end of the day, table tennis does require constant up keeping to maintain the level.
Even the likes of older players like Boll or Chuang (in there more recent times), would still practice to maintain, and during required times, to train full time. Then you have players like Feng or Dima who if take rests, would drop in form pretty fast - they need constant full time training.
So you have 2 kinds of players, one that need to train a lot, one that train very little, to "maintain".
To get
better after 2 decades after your peak- that is beyond my team of professional coaches and players know-how - we all trying to seek how to become better every day.
Olmo Zavala to me doesn't look like he has been training much or there is just a massive gap in playing level. But content of the video is indeed useful (however I am assuming it is based on a 1900 level beating a 2100~2300?)
Some info, his ITTF WR peak however, was 2001, when he was 500 odd in the world. and he retired in September of 2003.