Is it possible to throttle certain workspaces in a capacity

Hi. I don't think there is something like that. You could build an approach if you split your capacity. For example if you have a P2. You could have two P1 (one for production with auto scale and another for Dev or Test without auto scale). That should work. However if you have a P1 or F64, it might be difficul to reduce to two F32 because you can loose features.

An alternative that might help is considering scale out for some environments. You can read about it here: https://learn.microsoft.com/en-us/power-bi/enterprise/service-premium-scale-out

Consider that the best way of keeping the capacity sane is preventive actions, like good practices or rules for users to keep limits of what they can do.

I hope that helps,