Only as far as the first bottleneck though - if 1000 customers in a neighborhood pay for 1Gbps connections, that doesnt mean the neighborhood actually has 1Tbps

Only as far as the first bottleneck though - if 1000 customers in a neighborhood pay for 1Gbps connections, that doesnt mean the neighborhood actually has 1Tbps of capacity to the wider internet. Its probably a tenth of that at best, even in well connected areas.