It depends on lots of things… I’m looking at 1920x1080 on a 50 inch right now!
On the other hand, my main system is 3840x2160 on a 27 inch…
At computer monitor distance or TV watching distance? 
Setting up a mirror, and the older system happened to be located at the TV. You figured it out! 
It tries to run at 4K, but my eyes aren’t up to THAT, so off to the Display manager…
Today, I’ve had the fourth or fifth update in two or three weeks to linux-lts… If it goes on like that, in a five year span, they’ll need thousands of updates. 
There is without any doubt something fishy in this lts for a part of the users (some of the Optimus ones?).
Well… they have a lot going on: https://git.archlinux.org/linux.git/log/?h=v5.11.3-arch1
(This is for the default kernel though.)
And this for the LTS: https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.20
It is because the LTS kernel is currently at the beginning of it’s lifespan. The more mature it gets, the less frequently it updates.
I don’t know where to search for help, however running the 5.10 LTS compared to the 5.11 kernel, auto-start of my PIA (private internet access) app (on Plasma desktop) is much delayed and the PC connects to the internet before PIA starts up. So, being privacy conscious, I have to wait before starting a web browser, and generally speaking would feel more comfortable if PIA started as quick as possible.
I didn’t see this issue with the mainline version of the 5.10 kernel in previous months.
PIA said they didn’t have anyone else reporting this issue & my searches in the Arch forum have come up blank.
It might be a Plasma issue, but I think it’s related to the new 5.10 LTS kernel.
@RegularBloke, just use the kernel which works best for you. If the behaviour is different with different kernels, it’s almost certainly due to kernel. Keep both linux-lts and linux installed, and whenever they update, test to see if there are any changes.
Also, who flagged that post and why? 
I’d guess someone flagged it by mistake.
I flagged it because it’s not related to the thread topic and it should be moved to its own thread (e.g. “PIA app starts after network is up”). Unfortunately, I clicked “Off topic” rather than “Something else” and it hid the post, and I have no way of “unflagging” the post now. 
I just made it unhide.
If it is not too much to ask, could you move it, and the subsequent discussion, to a new thread, please? 
You could use openvpn with network manager rather than the PIA app.
I know on my setup I would lose too much speed that way (for me). PIA can use WireGuard, and runs decently quickly. I don’t understand the
slow startup, though - mine is running within a couple of seconds of login (or less) - immediately after Welcome pops up, there is notification of connection…