I don't know how much of a difference the pre-fab units will make. I think much of the issue is coming up with locations and getting coordinated with local power utilities. It is not unusual for a site to be finished and to set for 2-3 months until it gets turned on.Yes, I agree. It takes an awfully long time to get things going. I think Bracebridge was on the plan for at least 3 years before it finally was completed late last year. This is why the pre-fab units might help with the expansion. The other part of the equation is how Tesla is making decisions about expansion. Now that it's allowing owners to vote on locations - that might either be good or bad but it's unclear at the moment.
And other sites take many years to even find a location. Brockville has been an example of that as it has been on the map since around 2017.