I maybe proved wrong but I believe the majority of model railway/railroad modellers are not so nit-picky, that they would not use any item that did not exist in the flesh on their representation of such a line.
My Empire is loosely based on GWR/WR but I have no qualms about running locos that may or could or should have run on those rails & so to get another item which will make it look more like a rail network like RTR semaphore signals would be a blessing.
For those who follow the actual railway/railroad & must have the correct type of post, etc, good, but we must not forget that the hobby has a few compromises & to the majority of users; having the correct type of signal post would be a minor part of their enjoyment.