Waiting for the obligatory "Googler here, not on the Android team, but here's my totally personal opinion why this is actually a good thing..."
My guess is that people who juggle multiple browsers and who want actively want a null default are nonexistent but the people who are confused when opening links after installing a second app that works as a http handler changing the flow are.
I'm one of those nonexistent people. I have Firefox for personal use and then Chrome for work stuff. Depending on the app launching the link, I choose the browser myself.
The new work profile container stuff has somewhat reduced the utility of this but it's not gone for me yet.
Same story. Got four different browsers I work with.
I use MS Edge for trusted websites and the ones I want to be logged into and DuckDuckGo browser for random pages and news articles which are normally filled with ads and tracking code.
A better thing is the TWRP option to "format system partition."
In fairness, that easily can be an actual personal opinion; consider that "people who work at Google" is almost certain to be filtered to "people who aren't too bothered by Google's behavior" in the first place, and then they work in an environment that exposes them to the values that create Google's behaviors.
Also consider that people are more likely to vocalize what they think their company is doing well as opposed to what they think their company is doing poorly in a public forum.