Very helpful post. You are saying that I can keep my Chamberlain hardware the same, but use a different app?If you're talking about using MyQ for your garage door opener, you might want to look at the meross smart garage door opener.
I had myQ, with the bridge, but I had nothing but problems with it. I'd have to reset it every few months (maybe every 4) and there was always a lag when I hit the app to open it (or did it through HomeKit). At the end, I was getting a ton of errors saying that the garage was unable to be closed (I forget the exact message, but something about obstructions detected).
After I couldn't fix that, I moved to the meross one & wish I had done it sooner. It works much quicker, so no 10s second delay to open/ close, and it's been 100% reliable in the year that I've had it. And it was really cheap.
I have a LiftMaster Chamberlain 8550.