Regular Disk IO still will suck for servers that need decent performance using Luks. It was noticably faster after I left luks. Even windows bitlocker terribly degrades performance. I never heard of any organization using encryption for server operating system partitions.

VeraCrypt with an encrypted partition was way faster than Luks....and if a server uses debian and btrfs, apt performance is slowwwwww because of know issue with how apt/dpkg writes to disk with.