Losing a trademark to a generic word can make marketing a lot harder, though. A company often needs a new brand then, because everyone else can use their old brand in the marketplace.
It would be fascinating for Alphabet to lose Google the brand to being a generic word. (To be fair, it is something that maybe should have happened already.) Kagi or DDG or someone could use a domain like google.new or google.tech to easily retrain old habits of some users. What is Alphabet going to do in that case? If Google is no longer a trademark but a generic word, do they focus on having the "Alphabet Brand Google" or "The Original Google, by Alphabet"? Either way, that's harder to market and maybe easier to build a fresh brand than fight the generic terminology.