I paid 20 GBP to "buy" the Black Widow movie on Disney+. For two people watching, it was more or less the same price as cinema tickets, saving the travel costs and the obsessive munching of self-unaware viewers in the same theatre. IMAX would cost 50% more. I guess for some movies it would be worth to go for IMAX. But for most movies, I find paying 20 GBP for two people provides similar value and a better experience than going to the cinema (and I have a 30 inches monitor, so it's not some massive home theatre). If it's only you watching, then yeah, 20 GBP are not ideal.