The Olympics are in 2020, so I doubt if the results this year will impact his Olympics eligibility. He will likely need to do well next year to be eligible based on when the ranking cutoff is.
I come down on the side of the players professional success counting more than participating in the Asian games from the perspective of a player (and of course they may differ among themselves). As a player, I would value playing a GS more than competing in the Asian Games (although I would likely value Olympics game participation as much as a GS participation).
For Yuki, his decision to play the GS main draw over the Asiad is a no-brainer both in terms of professional challenge and also in terms of earnings especially given his stage of his career (also true for Rohan). For the qualifiers, it's a closer call but for someone like Prajnesh who may not have too many opportunities going forward even at the qualies level, it is certainly understandable if they chose to play the qualies with a chance to make the main draw. Of course, they would also have a chance to win a medal which they may value more. For others, who are younger, it is probably easier to play the Asian Games given that they may have opportunities in other Grand Slams.
