This may be an unpopular opinion: I'm very grateful for all browsers to switch to WebExtensions. To me, for the web to win as a platform, standards are a must.
I'm a new WebExtension indie dev. I just launched my first extension on the Chrome, Firefox, Edge stores. Opera is in review. Safari 14 took 15 minutes and 1 commend, just waiting for it to drop. I couldn't have shipped this quickly by myself if not for the WebExtensions standard. It leaves me time to focus on building what users want and telling users about what I built. Yes I did have to settle for less developer power and control. I'm totally ok with it.
Feel free to AMA!