About the "resistance to change" point, some comments:
- The thing that we can't change in Bitcoin is its primary properties, its fixed supply etc -- basically we can't do a hard fork. You're talking about "change" in general, but that doesn't make sense.
- If you're talking about change in the soft-fork sense then Bitcoin is easy to change, it has changed dozens of times, and it would change again tomorrow if Pieter Wuille and Greg Maxwell proposed a new cryptographic scheme, because everybody would immediately assume it is a good thing, like for example the immensely complicated "CISA" idea (which is not even a proposal because not even the brightest managed to arrange the pieces into an actual proposal) that would have to change some fundamental aspects of what constitutes a Bitcoin transaction -- that idea is already supported by 90% of Bitcoin users by default and would probably be activated with no contention whatsoever, like Taproot, which is another radical "change" that barely anyone understand even 2 years after. In any case, as long as these changes are opt-in and backwards-compatible they are harmless, and Drivechain fits the same category. It's a simple soft-fork that introduces a stupid counter that miners can change.