Mozilla is a no-profit foundation, not a company which needs to be sustainable or be profitable.
I agree Mozilla lost its way but I would still hope in them improving over time than trusting yet another for-profit to serve us in the long-term.
I think you and GP are saying the same(-ish) thing. A non-profit which has no money cannot continue, and so if it spends more than it takes in then eventually it will have to stop. This may be ok if it's part of the mission, or if they're hoping that a big donation randomly shows up. A normal business whose mission is to make money hasn't got those options.
Sure, but this sort of thing (email, plus likely mostly shitty calendaring and contacts) is a very ok business. The fastmail people make a fine living at it (their product is as good as anything outside gmail. If you haven't, you should try it! I'm a happy decade-long customer). But it's not the sort of business that supports the massive employee count that Mozilla has.
I might be misunderstanding the org chart but Thunderbird is operated by MZLA Technologies Corporation, which is for-profit (although I guess it's owned by the non profit Mozilla, similar to how openai was?)
they do in fact need to be sustainable and profitable. thats how numbers work. no one gets paid they leave. this isnt a charity.
NPOs still need to be financially sustainable/viable. They still need to pay their employees and pay their vendors.