Adam Funk wrote:

is there any reason not to
just put an RJ45 plug on one end of a piece of cable & the RJ45 socket
on the other end?

It's not impossible, but you're looking for a mixture of bits, normally
sockets expect solid core cable, and plugs expect stranded core flexible
cable.

Using flex in the krone punch-down of a socket *will* be unreliable
(been there had to fix someone else's ****-up) you can get plugs for
solid cable, but they're a little harder to come by, or you can get
plugs that claim to work with both solid and flex.