As others already mentioned, funding is just one factor here. Mozilla decided to stop focusing on porting such applications to the Web before 2020's layoffs, w

As others already mentioned, funding is just one factor here. Mozilla decided to stop focusing on porting such applications to the Web before 2020's layoffs, when Mozilla was still growing. The decision came after some management changes, basically: I don't think any individuals changed their minds, just those people happened to leave, and their replacements had different ideas. (I personally disagreed with the new priorities at the time, and ended up leaving.)