This is not a good trend

You are right. The answer should lie in recognizing that a trademark is a formal adjective. Many years ago there was “Mozilla Firefox” but also a fork “Frontmotion Firefox” and potentially others not using the Mozilla trademark. You could rebrand the software without changing the executable name or the heading in menus.

Sadly nowadays the branding is “Firefox”, or “Firefox browser” for the pedantic, but the program is not installed as /usr/bin/browser. This makes it hard to preserve the freedom to make and distribute any changes you want.