It would have helped the story arc to show how many prior sales per economy and plausible saturation level. Remember not everyone is displacing gas, or has solar power, the two lead reasons to move. Or, has access to subsidy: this could be government initiatives being oversubscribed.

People who live in tenements and flats and apartment complexes have additional barriers around siting and common property access issues. They bedevil this, and FTTP especially in heritage listed townscapes.

I wonder how the communal heating models are playing out in Europe? They have wonderful economy of scale, but not all of them scavenge waste industrial heat.