Vigilance. Resource monitoring and network traffic monitoring. The occasional scan with anti malware tools to catch known bad actors.
I use malwarebytes when someone needs a scan, though they got naggy enough that I uninstalled it right after using it for my grandfather. Other monitoring IDK. LittleSnitch is popular on Mac but I have no personal experience with it.
The etched glass is a significant value add. Matte protectors aren't comparable.
Whether that's worth the premium is up to you, but it helps a lot in harsh lighting.