@Erik Past Right. Ownership is how you get the Venn diagram of responsibility and authority to have higher overlap. Every organization I've worked in or consulted for (whether they were big banks or Bob's Bait Shop) that didn't have budget/mission/ownership alignment would go looking for bandaids like cost tracking in shared services after the fact.
It's OK to do that as an intermediate step, but it never really gets solved without executive leadership helping drive responsibility/authority alignment so that spend impacts the budget and incentives of the team causing the overburn.
Of course, it means that ops and shared services teams have to show value and make it observable to stakeholders, especially in relation to their cost. It's good, since serving stakeholders with features and reliability while showing RoI as a matter of course should be at the core of any platform engineering team's mission.
Some Ops, compliance, security, and internal services teams don't like/want to show value and depend on mandates instead. "If you build it, they will come." So there's a balance there, as well.
So. If the answer to...
• Whose money is it?
• Who's the one spending it?
...isn't the same person, then cost tracking and management efforts are doomed to fail over the long haul, putting greater burden on platform teams in the meantime.