Interesting conversations. I am a relatively new table tennis player (started in June of 2021). I've advanced to the median of my own local club. According to our league results, i'm one of the fastest advancing players at my club. I put in the work to train diligently, improve my weaknesses, fortify my strengths, study and implement effective tactics, and just overall be a student of the game.
I would also say that I am one of the most "athletic" players at my club. I lift weights at the gym in a circuit training type style. Do i think my athleticism has helped me advanced quickly (a relative term) in this sport? Absolutely. Has my athleticism helped me beat higher level players? perhaps, but it's not purely because of my athleticism. It's because my athleticism has allowed me to work on the things that I listed above that i believe improve my game. For example, you have to have a proper technique to loop against backspin. A great way to develop technique is to practice it thousand of times. if you are in better shape, you can practice longer and more diligently. Once you have developed the technique, you have to be able to implement that technique while on the move and off-balance. Being more athletic helps you train better on the move and off balance.
Another interesting point- i have migrated over to table tennis from another sport- soccer (or as some may say, futbal). Soccer, of course, requires technique and precision. athleticism provides a huge advantage in the sport. One example i always use is that a team of top in the country,10-year old soccer players would never beat an above average men's rec soccer (grown men) simply because the grown men are stronger and faster (more athletic) and the grown men would impose their will on the younger, weaker, less athletic, albeit way more talented in every way, top youth soccer team.
however, in table tennis, especially at the amateur level from what I have seen at the tournaments and in my own experience, athleticism does not matter *that much*. I've gotten my ass kicked by chubby dudes. By little kids. By all sorts of body types. It is quite humbling, and at my club, we often joke that in this sport, you can't judge a book by its cover, because the big fat book could really kick your ass lol.
And this brings me to my final point- at the highest level of this sport, there is no denying that athletic and physical prowess of the top athletes in table tennis. I remember seeing a video of the CNT playing soccer on the beach. all of these guys were in EXCELLENT shape. There is not a single person in the men's top 10 that is not a SUPREME athlete, not even counting their other-wordly pure talent for the sport. Even some of the top pro players that were posted in this thread as an example of "bigger" players were still in excellent psychical shape with way above average athletic ability. Wang Hao, even when he put on "some" weight still had extremely strong legs, and and extreme sense of balance and dexterity (both athletic characteristics). Or Liam Pitchford, this man is one of the skinnier top players, but he is agile, and extremely flexible. These athletic traits give him an ADVANTAGE in this sport, but are not the sole reason he is a top TT player in the world.
Of course, there is a limit to everything. In american football, it is common to see running backs to cut weight if they want to be faster and more agile, or put on muscle weight if they want to bulldoze their way through players more. Watch some videos of 360lbs linemen do cone drills. you wouldn't believe how amazingly these big men move with all the weight they have. They are undoubtedly supreme athletes. The best pro athletes will work extremely hard to construct their body into it's optimal shape and condition for peak performance in their chosen sport.
In Summary, there can be no denying that athleticism provides an advantage to table tennis players, or any sport for the matter. Look no further than the top 10 TT in the world as proof. However, in any sport, professional athletes are more of the EXCEPTION to the rules, rather than being the rules. There is a reason why they are paid to play their sports, and compete at a level that the vast majority never will. These professional athletes have the tangibles AND the intangibles. That is why they are the top in their sport. At the amateur. to high amateur level, there are so many factors that can make a player highly competitive or not. There are lots of examples of "unathletic" players competing and succeeding against more classically "athletic" players although i would argue they are displaying other athletic traits such as pure strength or reaction time. In this sport, being the fastest or strongest doesn't mean you will be the best player, even more so than compared to other sports like soccer or american football.