I think with these things, at some point one should cut one's losses and do whatever is most enjoyable/least annoying/worth the investment.
Find the rest of the game good enough? Stick around while ignoring the lootboxes (I've done like that with some games).
Find the game too annoying at this point? Quit, move on, switch to something enjoyable.
Find it still worth it even with the microtransactions? Well, there's a path to act in response to that too (but I am inclined to believe this is not your path).