the only serious argument for choosing chromium rather than firefox is for security reasons https://madaidans-insecurities.github.io/firefox-chromium.html
something funny is that to improve security, chromium needs to migrate to a memory safe progamation language and their best option is to migrate a part of the code to Rust, a language developed by Mozilla ^^' https://www.chromium.org/Home/chromium-security/memory-safety