One might consider Cloudflare as a very nice competitor to Vercel in terms of DX, although I suspect all companies use a ban the world approach, even banks.
Why would you assume independence? I'd expect an outage to put people "on edge" for a period of time following the outage, during which changes are scrutinized to a higher degree, and/or a greater engineering focus/budget is dedicated to reliability to reflect the changed business/image requirements.
