you can mine but you will be making a loss lol.
Agreed anyone buying 4090 to mine on would be absolute madness, no idea on their ability but would be sucking 450-600W for card alone so I doubt anyone will, plus the size of them means only one per machine, two at most. Plus they require high-end expensive PSU's to run them, they are not exactly a mining product, they are a flagship luxury goods product aimed at those wanting the very best and latest kit, lets face it for the majority of people a 3060Ti will play every game very well and cost £400, to play games well you don't need to spend £2000 on a graphics card and a few grand on rest of the system to match the GPU, but as with all things in life you can either buy a Skoda Citigo or a Lamborghini Aventador SVJ, one cost 10k, the other cost 500k but both perform the same task, taking you to places, its an anagram but as with all things in life people spend money on what they love and like, some women will spend £50 on a hand bag, others will spend £5000 or even more, but the task performed is similar. There is no such thing as a poor performing graphics card any more, even a 3050 will game at HD, but hobbies are hobbies and some people a 3060Ti will do everything they want, whereas some people want the very best even if they don't necessarily need it, there is nothing wrong with that what people do with their money is their decision, if people want to buy 500k supercars, 50k handbags or 2k graphics is their choice, just like others will go with the 5k car, £50 handbag and £200 graphics card.
I think the only issue will be scalpers attempting to buy up all the FE stock and MSRP product as I highly suspect availability on AIB MSRP product will cease to exist one hour after launch and will then ship in very small to none existent numbers afterwards. The AIB's will purely focus all volume on OC models that cost more than MSRP.
If the pound hits 1.20 next month, should not be an issue though as then OC models would be hitting MSRP or very close to it. The fate of the 4090 and its pricing is really in the hands of the UK government as it has such a dramatic effect on the cost of a product that has a $1599 price tag as at 1.00 that is £1599 plus VAT (£1919) and at 1.40 that is £1142 plus VAT (£1370). Essentially £450 difference simply down to exchange rate.
Though the idea of seeing 1.40 again I feel seems unlikely considering the pound over past ten years has got weaker and weaker over the long term, with just the odd spikes.