I hope not. Add-on signing is a glorified backdoor. Not only does it let Mozilla remotely disable extensions, but in future, governments can force Mozilla to censor unwanted extensions.

In addition, it is a privacy violation, since Mozilla can see who has installed which add-on.

In addition, when Firefox contacts Mozilla servers to verify if Mozilla approved each extension, it discloses to Mozilla which extensions are in use. So in addition to being a backdoor by definition, it is a severe privacy violation as well. This comes from an organization that perpetually claims to champion user freedom and privacy.

(source: change.org)

In addition, there was a certain May 2019 incident that we must not forget about anytime soon:

all Firefox addons have been disabled due to an expired certificate. And so, people got silently hit with stuff like this when turning their “private and secure” browser on. It was only a matter of time until Mozilla’s extension prison backfired, and it did so spectacularly. Though the BugZilla comments were already predictably closed, they will not be able to contain the armageddon this time, no matter how much PR they spew. The whole /r/firefox front page is filled with threads about this, with many people moving to Chrome-based browsers. Hacker News is also booming. Tech sites are running with the news too. The funny thing is, the whole point of the extension prison was allegedly to increase security - and yet today, all security addons got disabled because of it! Shows how freedom always has to trump over security or it ends up in a disaster like this.

(source: digdeeper.club)