Sooo, having downloaded the checker app and determined that my PC is not suitable for windows 10, I rebooted and went for a fettle in the BIOS. Eventually I found the TPM setting buried down in the Advanced section.
If you read the blurb that goes with this, you find that this is just intel's term for TPM 2.0. so I enabled that, checked that secure boot was enabled (it was) and then rebooted. The machine took a few seconds longer to boot up the first time but returned to normal after that.
Re-ran the checker and
The point here is that most recent motherboards will have this in one form or other, so there should be little or no requirement to go out buying new kit for this. Assuming you may be in a position where you are running older hardware that does not support TPM, there are little plug in modules available which will provide that functionality too - According to Scan, these seem to be retailing for less than £20, but you do need to ensure that you buy the correct one. Therefore, it's unlikely you'll be in a position where a new PC is required to run 11 - and there's nothing wrong with staying with 10 (or 7 Dave😉)
It's also worth noting that we're already seeing signs of an uptick in sales of TPM modules as scalpers look to cash in on those desperate to upgrade aging rigs.