It is in their business interest to ignore Firefox.
Then they aren't doing a very good job of it.
>Firefox makes up about 90 percent of Mozilla’s revenue, according to Muhlheim, the finance chief for the organization’s for-profit arm — which in turn helps fund the nonprofit Mozilla Foundation. About 85 percent of that revenue comes from its deal with Google, he added.
https://www.theverge.com/news/660548/firefox-google-search-r...
Hot take: Google keeps Mozilla/Firefox alive through the default search engine placement (which makes Mozilla millions each year) so they don't get designated as a monopoly with their browser.
Google is so internally fractured, and the factions individually are so powerful, that it's really only the chrome people who care about chrome.
If anything FF gets left out because usage is so low.