Precisely. If it was a truly innovative, no-brainer upgrade like dropper seatsposts, you would find almost one every recent-ish bike. I have seen one (1) live so far. And it was a ultra high end road bike.

For the same reason, what the pros do on their rigs is no concern for the 99.9% of mountain bikers.

I wouldn't bring anything I can't repair or troubleshoot directly out in the mountains, let alone anything that can discharge and not work anymore.