This becomes particularly differentiating when you start looking at batching primitives. Getting that pipeline filled up can add another 10x+ to performance.

Stacking all of the multipliers in your favor, things do begin to look pretty silly for distributed crap: Moving from a network trip in the same datacenter to an L1 reference is about a million times faster. That is pretty direct terms - you could hypothetically claim your app is ~6 orders of magnitude faster than some competing solution if you do everything right and you aren't saturated on I/O.

All of this said, I am feverishly pushing most of our B2B product stack into "serverless" functions. We don't need 6+ orders of magnitude performance improvement for our business. We need compliance, standardization and stability above all else. We want to be able to point our fingers at someone else and say "you fix it".

Running everything in 1 process is something I have been very enthusiastic about so far, but it does have its downsides if raw performance (or simplicity) is not your primary objective. We are trying to sell our product up-market, and without the ability to say things like "our production database is N+3/multi-zone, uses TDE and the keys are stored in an HSM on Mars", we won't get much attention from those customers.