Unless you're on dial-up or some kind of mobile network, you shouldn't be having trouble downloading even full blocks. It's only a couple megabytes every 10 minutes. Could be something else going on 

TBH I don't have any data and wouldn't know how to look.

I thought it could have been the RAM so I upgraded last year but still having the same issues. So its either the internet, or excess on chain data.

Do you have any data on this?  Inscriptions or not the block size has a max.