I don't think it particularly suffers from not having "good defaults", because it doesn't get adopted by word of mouth. And people are not shopping around The Best OS that they find, and sadly, they evaluate that Linux just doesn't have the juice.
Two things here.
One, OSs get adopted because of the package they arrive in. Laptops have Windows bundled, schools get computers with Windows on the cheap. Phones come with whatever they are integrated - often, not even a major upgrade is possible on them, let alone an alternative OS.
In my opinion, products like the Steam Deck are what get Linux adopted. They provide excellent functionality out of the box.
Two, PCs in this age thrive on interaction. Overwhelmingly, they are bought to interact with other PCs, either directly by network or through formats of specific software, like docx. Therefore, the functionality depends on how well they can participate in a network. This is where Microsoft really made it big with how ruthlessly they pushed Windows as an app platform and Office as the productivity software baseline.
Hence, in the end, what makes Linux really competitive today is the proliferation of web apps, because Linux has first class browsers, and the existence of Wine and its related software. Take these two away and the OS is not even talked about as an alternative to anything, just a specialty, or a curiosity.
Really, an alternative OS can do two things. It can either set the trend, which is not very likely, given that we are talking about alternatives. Or it can follow the trend, or "embrace" it, in MS lingo.
Some do come with Linux preinstalled, but there is a lot of mess in this regard. "Windows tax" was one of such things, the Windows bundling went so hard[0] that it was more expensive to buy a computer without Windows than with[1]. Absolute nonsense, that more or less stopped now. But of course we are well past the Windows platform establishing itself, so now the network effect is a larger contributor I'd say.
We all know about the Windows tax and Microsoft making Windows XP free for Netbooks.
OEMs making custom distros didn't help.
If anything that was the precursor of the Android distros mess that we got afterwards.
They also did the same with CP/M, MS-DOS and Windows since forever, including UNIX clones, why wouldn't they do otherwise with GNU/Linux.
As former owner of an Asus Netbook 1215B bought with Linux pre-installed, even that way wasn't without issues.
OpenGL support was always lagging behind what hardware was capable, GL 3.3 vs GL 4.1, hardware video decoding only worked during Flash heyday, and wlan drivers always had issues with hardware when doing large downloads.
OEMs were smaller than Microsoft, that was the problem I think. Valve seems to have success with Linux, which is maybe because of their niche, and size. Smaller players just don't get to be trendsetters.
Valve has failed to convince studios already targeting POSIX like environments like Android NDK and Orbis OS (PlayStation), to port their games to GNU/Linux.
Had to switch translating Windows games, as plan B kind of solution.
It remains to be seen for how long Microsoft will tolerate Proton, or just like it happened with netbooks, will drive other handheld OEMs to use Windows and thus in a decade from now people will foundly remember Steam Deck.
Two things here.
One, OSs get adopted because of the package they arrive in. Laptops have Windows bundled, schools get computers with Windows on the cheap. Phones come with whatever they are integrated - often, not even a major upgrade is possible on them, let alone an alternative OS.
In my opinion, products like the Steam Deck are what get Linux adopted. They provide excellent functionality out of the box.
Two, PCs in this age thrive on interaction. Overwhelmingly, they are bought to interact with other PCs, either directly by network or through formats of specific software, like docx. Therefore, the functionality depends on how well they can participate in a network. This is where Microsoft really made it big with how ruthlessly they pushed Windows as an app platform and Office as the productivity software baseline.
Hence, in the end, what makes Linux really competitive today is the proliferation of web apps, because Linux has first class browsers, and the existence of Wine and its related software. Take these two away and the OS is not even talked about as an alternative to anything, just a specialty, or a curiosity.
Really, an alternative OS can do two things. It can either set the trend, which is not very likely, given that we are talking about alternatives. Or it can follow the trend, or "embrace" it, in MS lingo.