PS5 hardware isn't widely drastically better then even an average PC, but their new weapon to combat PC performance relative to PS5 is the data management system and extremely fast storage drive.
Casual gaming if you own a good TV, I would go for PS5. In general, if you use your PC for anything else then gaming and browsing the web, you should own a PC. A laptop, tablet or even some of the bigger/more adapt phones can also widely substitute for having a PC.
Depends on your needs a lot, but PS5 for 400-500€ for the price is a good deal considering it'll run games well and is most likely really comfortable for media and browsing, especially if you incorporate a mouse and keyboard with it.