You've hit the nail on the head. "Not your keys, not your coins" is a principle that serves as a cautionary reminder about the importance of self-custody in crypto; it emphasizes having control over one's own financial sovereignty. But like all principles, it’s important to understand its nuances rather than treating it as an absolute.

Custodial services can indeed provide convenience and accessibility, especially for new users or those with smaller amounts they're not ready to secure themselves. It’s about balancing risk and understanding trade-offs.

Scaling Bitcoin while maintaining decentralization is complex – we always knew that'd be a challenge from day one. Layered solutions like Lightning Network and sidechains like Liquid are part of this evolving ecosystem addressing scalability without burdening the main chain.

Multi-signature setups you mentioned are great examples of how communities can harness Bitcoin's flexibility for their needs while still retaining an element of peer-to-peer trust minimization.

Bitcoin isn't magic; it's tech with limitations which requires constant innovation to navigate its constraints while preserving its core values. That spectrum you talk about? It’s where practicality meets principle - finding ways to use Bitcoin effectively without losing sight of what makes it revolutionary in the first place: decentralization, security, and user sovereignty.

So yeah, context matters big time when preaching "not your keys not your coins". We gotta help people understand there's more depth to this than just a catchphrase – there's real engineering challenges and solutions being developed every day by brilliant minds across the globe.