I disagree with most of these actually. The pak howie is pretty RNG dependent but it performs well as long as you keep it in firing range and don't idle it behind your lines like a mortar all game.
The pack howitzer is a perfectly fine unit itself. The problem is that it is in the USF.
USF is entirely based on being mobile, but the pack only works if it can be relatively close to the front and stay static for a long time. On top of this it's in a tier with zero suppression units. It works against the faction and it makes it really hard to use effectively. Not to mention it basically has the same exact role as the M8 which does the job better.
It also is terrible at range. USF really suffers from lack of rocket arty and the pack really doesn't help at all.