What you should be asking is whether the cables qre the bottleneck in your network or not.
Is there any link that is not negotiating 1Gbps? Do you have devices that could push 10Gbps but the cable is not allowing it? If not, then there's no need to upgrade them.
Unless, of course, if you want to do it just for fun, which is also a legitimate reason 😄
A 2 metre 5e cable will be a hell of a lot cheaper than a 2m CAT8 cable, and unless your internal network is faster than a gigabit or two there's really no point in using anything more expensivethatn 5e or maybe 6.