mach11, your question has stimulated wise responses, although that fact might not be entirely obvious to you.
Engineering solutions are usually the result of compromises made between conflicting requirements, and understanding those compromises is key to understanding the solutions. For example, priorities for a road vehicle are usually cost, ride, durability & handling in that order. By way of contrast, the priorities for a race (or "performance") vehicle are usually handling, cost, durability & (at a very low priority) ride, & this implies that a solution that works adequately for a road vehicle might not be appropriate for a race vehicle.
Suspension bushes are an example. They are cheap, quiet (tend not to transmit "noise") and are durable, but they have "parasitic" compliances (they allow translation as well as rotation). They work well provided that the parasitic compliances are small (i.e. parasitic stiffnesses are high compared with suspension stiffnesses). That situation can change if suspension stiffnesses are increased & accurate suspension control is required at high loads. The trailing arm bushes used in a "twist beam" rear suspension, for example, usually cause increasingly poor hub control as the damper "strength" is increased, resulting in unpredictable handling. Control will be regained by replacing the trailing arm bushes by "proper" bearings. I leave you to work out why that is the case....
"Golden" rules for converting a road vehicle for racing (probably incomplete):
1. Install a roll-over cage, & make that the vehicle structure.
2. "bolt" the engine to the chassis.
3. Replace bushes with bearings.
4. Stiffen structure that transmits suspension loads.