You still have to record them. Also don’t forget that if you have an ISA, other savings and investments that allowance isn’t that big.

As an individual if you mine you have to record the value as it was at the time of mining if you buy you record it at the time of purchase and you pay capital gains if you exchange the crypto for fiat currency or goods or services directly on the difference between the values. It gets more complicated since you can’t select an individual currency unit form your wallet but atm you are allowed to use creative accounting for that.

The fact that you have an allowance doesn’t mean it’s not taxed and if you have any substantial amount you’ll blow throgh that allowance pretty darn fast.