I honestly don’t understand why people buy the plastic razors when it is neither more convenient or cheaper.
Exposure is definitely a big part of it. The only reason I'm using one is because some podcasts / YouTubers I liked were extolling them and I looked into it. I can't recall ever seeing a safety razor for sale at any big grocery or drug store. I guess I could have just missed them. But they stock what gets advertised most, and by an immense margin: The dodeca-bladed monstrosities in either pussycat pink or blackout tacticool gunmetal. AFAIK, that's what everyone I know uses. I get asked every now and then if I can recommend my barber for a shave, then I mention the safety razor, and most guys have no idea what I'm describing to them.
Also, no matter the design, safety razors have an air of "old fashioned" that I think most people just cannot appreciate now. The notion that they'd ever have to do anything besides use the product and send it to the landfill is enough to make most people nope out immediately, and here you've got disassembling, reassembling, replacing parts, proper disposal... All that takes time and attention that most people can't reconcile.