Would making the energy weapons deal fire damage be a good balance change?

A while back a youtuber named Po10tial made a fairly well thought about how a simple balance change Valve could make is having the grordbort weapons deal fire damage instead of bullet.

Basically his main argument was that many of the worst weapons in the game rely on fire damage a damage type that only pyro really uses while most of the grordbort lack any real use case so having them do fire instead of bullet damage would be a basic solution to both problems and add some more strategy to the damage types

Now obviously the afterburn for most of these weapons should be kept pretty limited (maybe like 2 seconds of afterburn) and weapons like the pomson and bison would still need buffs to their projectile speed to be even remotely viable but I don't see any inherent issues with make the laser weapons do fire damage.

Link to the video