I've got a stock Ubuntu 18.04 install at work. Sometimes, but not always, it hangs for three minutes or so trying to run fsck on my UEFI partition. Other times, I'm at the login screen within a minute of turning it on.
When it hangs, it finally exits with an error message saying it couldn't mount /boot/efi. Once I log in I can see that /boot/efi is mounted fine.
A bunch of my applications hang all the time for reasons I couldn't figure out. Turns out they were trying to communicate with my Gnome keychain over D-Bus, but they were in a separate D-Bus session so they just sent their D-Bus message and then waited for however long until they gave up. No idea at what point this started happening or why, but I never did figure out how to fix it (other than disabling those apps from being able to store passwords securely).
If I used the Intel drivers for my Intel GPU I got extreme stuttering and tearing, which only went away when I uninstalled the Intel drivers entirely so that it would use the "correct" drivers.
Then there's snaps. I install stuff and sometimes it's a package, and sometimes it's a snap. If it's a snap, everything turns into a giant mess. I had Firefox saving its downloads to Skype's workspace for some reason, multiple Firefox profiles on my system in various places, multiple versions of Firefox running when snapd downloaded a new version and symlinked it to be the default, two copies of Telegram for some reason and no obvious way to tell which was which, a snap and non-snap version of things because the Store installed the snap but another package depended on the apt package, and so on.
I installed my system on btrfs because "it's like a decade old now, it should be fine right?" and within a month my filesystem had been completely corrupted and I had to reinstall entirely (though I managed to salvage most of my home directory at least).
This is all stuff I'm willing to tolerate to some extent, but I can't think of a single thing that Linux offers me that makes it worth all this hassle. At my last job, I happily used a MacBook for nine straight years, and I never lost an entire day of productivity just because suddenly my system won't boot, or dealt with graphical glitches in every app because the driver for my video card isn't the right driver for my video card, or lost data because one of the default options for installation filesystem is unstable and unreliable.
I've never had to do much of anything to "tweak" MacOS unless I wanted to; on Ubuntu, I have to do it almost every day to get something working well (or at all).
So I'm gonna go ahead and say that yeah, MacOS isn't even remotely dead, and it's certainly not going to lose to Linux any time soon.