WTH can’t I format the output of floats in cards

I have an integration with a spuriously accurate sensor giving 4 decimal places for power. I want to round it to one decimal place, just like all my other power sensors when showing it on the dashboard. I don’t want to define another sensor rounded down just to get there.

Why is this not possible without a custom card?

Looks like a duplicate of WTH can't sensor values be rounded without templates?

Closing as a duplicate of the above. Please vote there.