To some extent, it seems like a majority of CPUs is “vulnerable”, however it hasn’t been a big mainstream threat, yet.
I’m pretty sure you should only worry about it, if you have secret government documents or perhaps secret formulas or documents for an extremely important company on your computer.
However, if that were the case you probably would be on a custom machine, that doesn’t have any known vulnerabilities, anyway.
So, if you are a normal user, which you probably are, you have nothing to worry about, as in, you don’t need to change anything about your computer just because of this vulnerability.
Just stick to the rules of how not to get malicious software onto your computer. Stay away from shady websites, never click any ads and, most importantly, turn on your brain when something shady happens. People too often believe the unbelievable because of wishful thinking syndrome…