Can a Signature Base System Be Effective in 2023?

The way AV work is they go through an index, all the files that are coming in that you download and see if they match any of the known fingerprints for bad files. Windows Defender does a really good job at keeping that up to date as much as possible. It's rather easy for an adversary to kind of go around that or get around it by making enough modifications that the signatures brand new.