(Mozilla dev here, not speaking for Moz)
"grab telemetery" - that data is really, really useful in making development decisions, and we are hyperparanoid about what we collect. From an armchair, it may seem like you can make the right guess about how to eg adjust garbage collection scheduling priorities, but actual data always surprises you in one way or another. It can make the difference between spending a month on a tough project that ends up making no difference for the vast majority of users, and having a month to spend on something more impactful.
I really don't like to speculate on executive pay, but I'm pretty baffled why this is seen as such a big deal. Your argument sounds valid to me. So does the argument that we're talking about the CEO of a tech company that is competing directly with multiple Big Tech competitors, and perhaps paying comparatively bargain basement prices is not the smartest idea. Which is not to say that I'm happy about the layoffs.
Mozilla has messed up on a number of things, multiple times, including at least one time when it ended up (as in, made a deal to and carried it out) sending a bunch of data to a third party. (It was more nuanced than is generally appreciated, but I won't go there.)
I sincerely apologize that Mozilla isn't up to the pristine standards of the big technology companies. /s
I'm not going to explain the MoCo/MoFo structure here. I'll just say that MoCo most definitely pays taxes, MoFo asks for donations because it's a nonprofit with its own initiatives and direction, and you can get tons of information about the finances involving both because of MoFo's nonprofit status and the resulting annual report. (MoCo = Mozilla Corporation, MoFo = Mozilla Foundation, MoFo owns MoCo.)
The Google deal is, like, how MoCo makes money and is able to exist. What's shady about it? I'd certainly like the funding to be more independent. Maybe Mozilla can try drilling for oil on the land it doesn't own or start selling off the user data it doesn't collect?