People expect e.g. their "daily power consumption" to end at midnight local time. When they zoom in on the daily aggregates, they don't want a spike to suddenly disappear just because it belonged to the next local day and you only stored UTC-day aggregates. Even more so for billing.
The problem is that if the originating system didn't record the time in utc, you've lost the information needed to make the time unambiguous. What's 2022-11-06 01:30 USA/San Francisco in UTC?
