That article doesn't mention what the terms of the deal are. Mozilla has lost marketshare since the last time the deal was made, it's possible that the funding was cut as well.
Then it was a negotiation tactic. Mozilla showed that they don't desperately need the money because they are willing to cut all expenses. Thus, Google can't play the 'take whatever we offer or you will be bankrupt in 2021'-card. Firing the developers should have led to a better deal and they can now silently rehire them back.
That would work a whole one time. Not next time though. I don't believe that's what they were doing.
I think they were using the funding excuse as a way to cut staff without looking like bad guys. Reality is they were already deep in talks with Google on resigning and did the job cuts before finalizing.
They're probably doomed if the exact correct choices aren't made, I'm in that unpopular crowd that believes they should find a way to graft Firefox's presentation and features on top of Chromium to save on Gecko maintenance costs, and then continue to monetize with side products like their VPN and Rust (consulting). They should sell Pocket.
Marketshare gains will take time, that's a long hard road but it'll be based on features and privacy. If Microsoft couldn't hold off Chromium with EdgeHTML, then a smaller player won't be able to. There's still Webkit if de facto standards are a worry. Mozilla isn't the well-positioned, deep-pocketed player that should be offering choice in the rendering engine market.
I assume it followed an attempt by Google to influence how these funds are directed at Mozilla. Is Servo a threat to Google? Perhaps reinventing everything in Rust is just a detestable waste of resources?