I mostly text on Signal with disappearing messages so I wouldn't be able to do this. Most people are fine with disappearing messages at 4 weeks, but a few people like to keep their chats forever.
Do you keep separate notes for things like recommendations or addresses? I often dig through my chats to find them.
there's a tool for extracting chat history from signal desktop, you could build a plaintext and attachment archive with that if it runs regularly on your pc and appends new chats from the last run.