Ryzen is fine for home servers - you can even find boards that support ECC with it. I wouldn't bother with ECC for a media server - just keep good backups of your data if your really worried about it
The only non-replaceable data on there is photos I take (generally holidays/personal events etc), but I back those up to the cloud too anyway.
I think my biggest issue, is I don't fully understand the actual effect ECC has, and therefore can't decide on the risk. I get that it's to protect from memory bit errors, but what would the error actually cause & how often are they? For example, would the error merely cause a slight system slowdown, or could it cause permanent damage to the data being processed (I'm thinking the latter is less likely, as if it was, surely desktop PCs would use ECC too).
Remote management & multiple NICs are the other major thing you'll find on server level boards.
Personally, I wouldn't run anything storing important data without ECC & a VM always gets a dedicated physical NIC if it's doing anything remotely intensive.
In your case, as you've had to ask, I suspect you probably don't need these
I already have a separate dual NIC (PCI-E) in the server, so I'm not too worried about choosing a server board to have it built in.
As you've suggested, I'm pretty sure a desktop setup would work fine, I just like making fully informed decisions
28GB of RAM?? That's weird number for 'few VM's', so assuming you have 128GB and VM's needs to run 24/7..
In which case I would use ECC.
If you run home lab and VM's are not 'production' loads I would not be bothered with ECC
28GB is a little odd, but it's correct. The server came with a 4GB stick, and I managed to get my hands on 3 sticks of 8GB RAM to add to it (the T20 requires un-buffered ECC, which is fairly rare & expensive when I was looking, so I took what I could get). I generally run at ~40% usage, raising a bit at times. The VMs are production as far as they fulfil functions I use, rather than for tinkering, but aren't particularly critical, although generally run 24/7 for convenience.
EDIT: Just realised 28GB is incorrect (and I didn't notice my maths was useless). I have 28GB "usable" according to unraid, which is what I normally see, and therefore what got stuck in my head. I have 32GB actually installed.