The other thing which is not protocol related, is that companies can
help themselves and help Bitcoin developers help them, by working to
improve decentralisation with better configurations, more use of
self-hosted and secured full nodes, and decentralisation of policy
control over hashrate. That might even include buying a nominal (to a
reasonably funded startup) amount of mining equipment. Or for power
users to do more of that. Some developers are doing mining.
Blockstream and some employees have a little bit of hashrate. If we
could define some metrics and best practices and measure the
improvements, that would maybe reduce miners concerns about
centralisation risk and allow a bigger block faster, alongside the
IBLT & weak block network protocol improvements.