I understand and agree with your initial post.
In the studio, hours could be spent with mic placement of multiple mics getting a good drum sound with no phase issues. There are all kinds of ways to mic drums, some much easier than others.
When it comes to micing a bass cab, the process is not necessarily that difficult or time consuming. Time is not a good excuse. Often a single speaker is mic’ed. Some tests can be done to determine which speaker sounds the best but this isn’t a big deal, it’s done once. Often the speaker is close mic’ed, more towards the dust cap reveals the higher frequencies more. Placement is based on the sound that you want. Some people simply place a mic on the floor a few feet from the cab. No question the the sound of the speakers can be an important part of your sound. Some people even use more than one type of speaker cabinet to get a blend of sound.
I like DI’ing and using a mic at the same time. The mic provides a unique sound with some air. The DI can fill in for the weak spots in the frequency spectrum such as low frequency rolloff of some mics. I see both approaches as being useful. Live you may need a box (for example,
Phazer - Radial Engineering, in the 70’s the Eventide 1745 digital delay line was popular) that can compensate for phase issues between the two. If the sound person doesn’t have this, they might opt to choose a DI.
As for DI’s, there are more than one type, capable of capturing different parts of the signal chain. A basic DI that connects to the pre out is at one end of the scale. At the other end is one that captures the contribution of the power amp such as a Countryman 85, a Radial, or a Neve RNDI. Kick it up a notch and you have products such as Torpedo Live or Studio which have a dummy load and impulse response cabinet and mic simulators.
Maybe bass players need to consider taking a more active role in how their sound is conveyed. There are many approaches.