One size certainly does not fit all.
However it is not just how much a server costs, that is very simplistic view (a general case, not necessarily discussing GitLab here):
Cost to procure the server (the procurement process takes time = money).
Time to get the server to be delivered.
HW support contract.
Cost to physically install the server with associated DC, rack, network, power and cabling costs. Never mind the technicians performing the above needing salary.
Put together some orchestration system. (OK, one is needed in 'cloud' (eugh, I used the word) environment, however it will be using bunch of APIs).
Cost of storage subsystem (that can easily go into tens of millions depending on scale required).
Cost to repeat above in different locations and pay for the storage and network connectivity between sites (assuming stretched metro cluster, I agree Ceph is different animal).
On the other hand properly done public 'cloud' (eugh, I said it again, maybe should use equally disgusting 'hyperscaler'):
Adding the ability to scale as and when needed on demand.
Security model which is better than what most outfits can do.
OPEX which most FDs love as oposed to CAPEX.
This will work for most businesses, however to repeat one size will not fit all.
Of course YMMV.