The older machines can be cleaned thoroughly and must be oiled.
The newer machines I use all the time must be oiled too. I go by the manuals. I clean all the lint under, around and above the bobbin, as far as I can reach to the right, behind the bobbin area. Once in a while I take screws out of the bottom and clean and vacuum that out too. Just don't take the top of the machine off. I did that once and messed up the fit. Had to take it to a shop and have it put back on. I never take these to the shop. I will if something goes wrong with them.