Guess you have to take it as a given that today's F4 would have enjoyed some upgrades like bigger engines, better RHWR, better ECM, better radar and, not least, ASRAAM and AMRAAM.
If one accepts that premise, the old bird would do quite well and take a few scalps at long range but the crew would have to very careful to run away bravely before taking incoming.
One advantage it would have over many modern fighters is two crew members.