You can use tracks instead of wheels to minimize axle-bearing failures related to giant cannons pounding out shells.
You can use manual transmissions instead of automatic trannies to eliminate transmission-cooling hoses to reduce tranny-fluid-related fires.
You can use rockets (e.g. Katyushas) instead of cannons to minimize damage from blast-firing vibrations.
...but even doing all of that, self-propelled artillery has fatal weaknesses compared to towed artillery.
Towed artillery was and remains cheaper to build and maintain.
Towed artillery is also lighter and can be taken to places that self-propelled guns cannot reach. Since the Vietnam war, heavy transport helicopters have also been used for rapid artillery deployment.
You can do that with cannons. A helicopter can carry a howitzer.
Not really the case for 55 ton SPA’s, though.
What’s faster for “rapid deployment,” a helicopter carrying a howitzer landing on a hill in Afghanistan, or a self-propelled cannon driving there?
So in speed, cost, and durability, the towed artillery always beats self-propelled artillery. Helicopters are simply faster than trucks.
We tried the "make one howitzer do everything" silliness with 155s and that's just stupid. The beasts are large, bulky, heavy, and hard to find enough geography to deploy and the ammo piece is 90% of the logistic load for a division. Our bean-counters have tried for years to show that making one gun do all save us money and fights all enemies in all situations handily but that has always been poppycock.
We still need and 105/120 medium-caliber expeditionary high rate of fire direct support howitzer for mobility and responsiveness and we will still need mass and reach and flexibility in our GS weapons.