I need to get the owner of a NFT at a certain date.
I could just dig through this NFT's transaction history, but it seems a bit cumbersome.
Is there another way?
No, there is no other way. Digging through the transaction history is the way to go.
You can automate that by creating a bit of JS/TS code, of course.
When the history is long and/or you have a lot of NFTs to track, you can easily run into rate limits with the standard RPC endpoints, so it might be a good idea to get a private RPC node from vendors like QuickNode or GenesysGo. Some have free tiers as well.