We have vegetable oil for example and algaes can produce oil as well. So we do not need to dig for fossil fuel, there are alternatives for lubriaction and similar problems, were oil is very much needed.
Im not certain how well plant based alternatives work for the specific formulations needed for most lubricants, but honestly given the scale involved it doesn’t really matter if we use ground reserves. Most machines use gallons a year or decade, not per five minutes like cars.
Yeah, it’s the mechanical properties of non-crude lubricants that’s the issue. Maybe scientists could find a way to turn vegetable oil into industrial grease, but I have no idea if that’s even possible.
But like you say, lubricants aren’t the main problem; it has always been fossil fuels.