Here's an easy question.
How can TKD beat BJJ with TKD, if TKD has never sparred against BJJ? The only way to find a TKD answer to BJJ is to do a lot of sparring, using TKD against BJJ. It may require that you dig deep into the system.
How many times did your TKD training have you spar against BJJ?
How many times did your kick boxing training have you spar against BJJ.?
Things only seem like warp speed when the knowledge is not readily available. The things that I learned about Jow Ga kung fu are things that took me for a long time. But that won't be the same for my students, my students will be able to learn those same techniques within a year easily. The only difference is that the knowledge wasn't readily available to me during my journey which is why it took so long for me to use. While jumping from one system to the next works for you. For other people who have a passion for the system they train in. Jumping around isn't a good option as it won't help them to understand their system more.
The more MMA that I see the less I believes this to be true. MMA fighters tend to use what works best for them and the announcers often highlight this preference that the fighters have.
My guess is that any improvement in a technique is done by someone who isn't hopping around from technique to technique just because they think their technique doesn't work anymore. I can't improve Jow Ga techniques if one day I decided that they don't work anymore so I take another martial arts instead. You can only develop something that you have commitment to. If anything, MMA has a good record of showing that the old stuff works.
This is not TMA starting to look more like MMA. What we are seeing now is what TMA has always said was possible.
The majority of the techniques used in the video below existed in TMA and old grappling systems way before the MMA that you know, existed.