The bigger problem in my opinion is more about the fact that all elections that select a single winner will always end up in stupid degenerate systems like this where flaws and imperfections exist.
The best thing to do (again, my opinion) is to abolish all single winner races and have multiple winners with proportional representation. Get rid of directly elected presidents and have a prime minister selected by a proportionally representative parliament instead. All presidential systems suck, and the larger the number of people voting, the harder and harder it sucks. It's not just a USA problem - you also see it in France and Turkey, where they also have an all-powerful president that is elected nationally and the election is a complete shit-show every time without fail. On the other hand, having a prime minister selected as the head of state from a proportionally elected parliament is a much fairer and more stable system in my opinion. It has downsides too of course, but nowhere near as bad as nationally elected presidential systems.
In any case, the example you pointed out is a potential flaw in approval voting, but I don't think it's very likely to happen. First of all, it would require all those voters in the second round to conspire a particular way, which isn't very likely. Secondly, there's the fact that the numbers would have to line up in a very particular way which has a very low probability of happening - tweak a few numbers here and there, and the spoiler effect vanishes. Sure, the scenario you point out is a hypothetical flaw in approval voting, but I think it's a much smaller effect and probability of actually influencing anything - definitely nowhere near as much of a strategic voting effect as in plurality voting systems.
I don't like systemd mostly because it gives Red Hat too much power over the Linux ecosystem. For example, udev and logind used to be independent components that were eventually merged into systemd, and the onus was put on the community to maintain their independent derivatives (eudev and elogind). systemd's original developer (Lennart Poettering) has been very open about his intention to make life difficult for anyone that doesn't adopt systemd (source and original quote).
To me, systemd is the Google Chrome of Linux - it tries to make life easier and does a good job of that, but it's also explicitly designed in such a way to push out all competitors. So I avoid it at all costs and prefer other distros like Devuan, Void, Alpine, Gentoo and so on. That said, I don't do enough to contribute back to those projects, so I wish I were more helpful about it than I actually am :-(
Regardless, this doesn't mean that you need to do the same thing. If you're new to Linux, use whatever makes you happy and your life easiest! Practically none of the non-systemd distros are particularly easy to set up and use (Devuan may be an exception, but is likely the only one). And besides, a lot of this stuff is very old, and Poettering hasn't even worked at Red Hat for multiple years now.
But do keep in mind that systemd was a very political topic and still poses a threat to the Linux ecosystem - anyone could take over the project and leverage it to make life difficult for anyone that doesn't want to do things the Red Hat way. And since many of the major distros have made it the only option at this point, they'll have no choice but to be dragged along with it. Keep that in mind as you gain more experience with Linux and think about trying alternatives.