Nowadays old-gen server hardware can be a viable alternative to a new HEDT or workstation, which would typically use top-of-the-line consumer parts. The price and performance are both broadly comparable.
No. Up to you to cool. I use an Epyc based system as a home server and you can’t hear it. At a previous employer we built a cluster out of these and just water cooled them. Very easy.
This is a chassis and fan problem not a CPU problem. Some devices do need their own cooling if your case is not a rack mount. E.g. if you have a mellanox chip those run hot unless you cool them specifically. In rackmount use case that happens anyway.
