It's the reason I went for the disc console, at the very least I can trade/sell games I'm done with to take some of sting out of £70 games.
I have been lucky, I've kept my eye out on the market; and managed to get Demon's Souls and Sackboy for about £40 each sealed. At that sort of price I'm more than happy to pickup a few next gen titles. £70 does feel a bit too much for a single title though, no matter what Sony says to try and justify it. I realise the console is costing them a lot, but with console prices and lack of availability at an all time high; and every other platform charging less for new titles; it does make it a bit of a hard ask.
No way I'd have bought a digital only machine though; a large part of the incentive for me upgrading was the PS4 Pro-esque backwards compatibility library and the option to buy physical and resell if I want to; as well as PS exclusives being less likely to hit PC (even though a few recently have).
Digital is great for title like Animal Crossing on Switch which kinda 'lives with you' but for the majority of titles, physical still just feels better and gives you more options; especially as digital isn't any cheaper to offset the downsides.
Still keeping an eye out for a sealed copy of Miles Morales ultimate edition; I never got round to playing or picking up Spiderman on PS4, so really looking forward to playing both in the remastered forms.