Mac Mail is a great app IMO. It's full featured and performant, I'm very happy with it. This is pretty much the only issue, and it's only with Gmail.
I put up with it because I’ve used Mail for many years without issue until now. Fortunately for me it happens infrequently enough that it’s mildly irritating to me so far. Much less irritating than when I open my MacBook and receive dozens of iMessages at once along with their dings.
Mac Mail supports the Exchange proprietary HTTP API, while all the other clients only support IMAP. HTTP is much more efficient and seems more resilient against temporary network issues (due to the lack of a persistent connection).
Thunderbird sucks because, last time I checked, it had no way to copy or propagate filters between machines. Deal-breaker right there.