I feel like "perfect is the enemy of good" only works when you (still) have to put considerable effort to make it better, e.g. when building software.

However currently there are already better alternatives than Signal, so in my personal opinion I feel like that saying does not apply.

It's very fine if you (and most people) are OK with sharing some personal information with a United States organization. That does not mean that everybody is fine with that, or that it's a very good solution to a chat service problem. I'm glad that Signal is a good match for your needs. But there are those of us who would rather see a decentralized service with which no personal information has to be shared.

In these kinds of discussions, I often find it a little strange when others decide that a certain solution or product must be good for everyone only because they are fine with it themselves.