This issue popped up two years ago in the playoffs and was never properly addressed then unfortunately.
Last year there were about 20-25 games out of 375 that were played with OOB rules. Most of those games involved a small handful of players who clearly prefer OOB but were nowhere near the playoffs so it wasnt an issue last year.
This year There were 16 out of 350 or so games played with OOB rules with 11 of them played by one player and a few other random games. Thought this year is complicated because of the addition of P2V which actually represented quite a few games.
Just to put some numbers in. But for the most part I think this conversation was sidetracked.
In 2018 this issue came up in the middle of the playoffs. Thankfully it was avoided in main bracket in 2019 (though it came up in second bracket). Im trying to avoid dealing with this issue in 2020 as I know I wont be the only one who has an issue with this rule and so trying to start the conversation and deal with it before games are started. Its not a question of what the rules say, as that is clear, but the rules clearly (in my opinion of course) dont reflect the current league climate and opinions. I think the rules need to be adjusted for 2021 at minimum.
If the rest of the main bracket is fine with things as is, then all is well, if not then I think its worth discussing and dealing with ahead of time.