I do and it’s fine.
I used to have a separate machine for server stuff but it just cost more in electricity since I would leave them both on 24x7 anyway.
I’ve got 64G of ram and I often use up to 48 of it with various VMs. I wouldn’t get any power savings with a separate server since I have a cron job to transcode everything that plex recorded off of TV during the day to av1 for disk space savings (usually turns 3GB of mpeg2 into 700MB of av1), so I would need a server with a moderately powerful cpu anyway for that.
I have a ryzen 3700X. got it since it was the highest performance that was still 65w tdp at the time, didn’t want to spend a ton on electricity and extra air conditioning since I would be leaving it running 24x7.
The only time I notice a performance impact during gaming is if my windows 11 vm is running, I don’t really need that one running 24x7 so I shut that one down if it happens to be running at the time.
I’ve had good luck with goharddrive.com. They sell through amazon as well, but I believe they ship direct. I usually get the hgst, or now wd, ultrastar hard drives. I’ve had zero issues.