These numbers do seem in line with the propensity an average user has to switch default apps. I often compare this to how many people out of 100 bother to change their shoelaces on day 1. I'd wager less than 1, due to the friction of effort, configuration and learning curve, whereas the original usually just looks "nice", more "in place", "fitting" the decorum. Big icon is sitting there already.
Thus it's useful to consider market shares for all end-user internet-browsing devices, wherein x86 today is dwarfed by mobile and general ARM. The fact is you can pretty much correlate browser market share¹ with OS market share (which I guess retrospectively validates the anti-trust case against MS in the 90s).
- IE dominance throughout the x86 era (until early 2010s),
- then stratospheric rise of Chrome as Android took over 80-90% market share on mobile and probably 3-4x as many devices as Windows. Chrome took over everything else.
- Safari steady around 5%, about half of Apple's market share in both x86 and mobile (as low as half is surprising to me: since all iOS devices use Safari, the discrepancy between Apple's market share and Safari's must come from x86 MacOS, and I would have expected much more people to use default Safari on that OS, especially given its battery optimizations, compounded by Chrome's relative cost in RAM etc).
- Firefox is at an all-time low (still second though). Given the current trend of OS makers to expand into "ecosystems" (multiple devices/OS + cloud services), I don't find it surprising: mainstream users are more and more entrenched in the more-or-less walled "gardens" of each variety.
Clearly, Google is winning that game as of 2020 in terms of numbers, but Apple is winning too within its own (much smaller but more profitable!) userspace / customer base. MS is but failing so far, TBC, but meh it's Chromium underneath.
[1]: https://www.youtube.com/watch?v=es9DNe0l0Qo
