If you've been given taxi clearance by GMC then you'll have an unrestricted route to that holding point unless otherwise stated by GMC.
No you won't! Certainly not at busy airports. You'll have a route to that holding point, but not unrestricted. OP is correct, rules of the air still apply. While GMC will issue give way instructions these will not necessarily conform to the rules of the air since we'll be trying to juggle you into the most appropriate order for the AIR controller taking into account slots, SIDs, delay already taken, etc. If you haven't been told if you have right of way then follow the rules of the air.....
There's a reason we don't say "Clear to taxi..." and this is it. Unless the phrase "Clear" is used it is not an ATC clearance -btw, this is also why we say "pushback approved" and not "Clear to push".