You can just 0% finance a GPU+PSU upgrade like many do, it's not hard and it's an easy route to bump up your credit score as well.
But the main point is there aren't enough games that NEED a 40 series to get the best out of for that kind of money, something that for all intents and purposes ---if we sideline DLSS3 for a week or so until the reviews are out that deep dive all over it-- a 3080/90 series will fly through anyway and which most will already have anyway who are serious about higher end scale of gaming in the handful of games that command that sort of power currently.
If there were a shopping list of games that absolutely benefited from the new power then sure I could see the point (assuming all of nvidia's claims turn out to be true, which at present doesn't seem that way but we will have to wait on reviews). A handful of upcoming games is not reason enough to be buying £2k graphics cards when not even a year later the [prices will be dropped almost certainly in a big way to make room for the Ti cards, and if the rumours are true that AMD can introduce their new cards at an undercut price too.
If that is the case then nobody is going to be parting ways in 2 years time at 50% resale value lmao.
Buy smart.