The mass of people attending car audio competitions are those who have a system, whether it is decent or pretty loud. There is a small percentage of people who actually compete to the point where they have strictly spl subs and spend hundreds upon hundreds of hours finding out exactly what the best drivers are, what the best enclosures, etc to use for their vehicle. That doesn't mean that the majority of people don't spend the time to figure out whats good for their car, but usually people go with what they think or hear are good amps, subs, etc, have a nice box, and do some EQ-ing and whatnot and it is intended for daily driving.
The OP did not mention anything about sq, but mention crisp and clean sound, which strictly spl subs do not offer. Loud is also a relative term, I have people telling me my system is the loudest and best they have heard when I know it's nothing near the best. It sounds good, gets fairly loud, especially at lower frequencies, and at times i find myself wanted it to be a bit louder. As mentioned before, with dB Drag, it's more about what's loudest on the mic, not to the ear. What may sound loud to the ear may not be equivalent to what is loud on the mic.
All this bickering back and forth is pointless, some people fail to see that you don't have to be loud to be happy. If person A like stupid loud systems, and person B likes extreme SQ with a defined frontstage, whats wrong with that? Who's right here? Who's wrong? NOBODY! People are taking car audio in different ways, the definition of car audio isn't loud, isn't sound quality, it's what you want it to be, what your preference is. Just because you don't agree with someone else's preference doesn't mean its wrong and the opposite is true as well, your preference isn't the best. Car audio has many variations, just leave it that way.
But plain and simple as someone else had mentioned, you either have sq or spl, but you dont have to have an all out spl or sq system, you can have a bit of both, but at the same time you will sacrifice the other.