Depending on your definition, this actually is not peak performance.
Subways are.
Obviously, the tunnels are absurdly expensive, but nothing moves as many people as quickly around a city as a subway.
They're also extremely reliable, meaning people are even more likely to actually use them, and their above-ground footprint is essentially zero.
It's the quiet part that's (usually) not said aloud.
Just take a look at the statistics of how i.e. criminal law is applied much more aggressively to conservative out-groups (PoC, poor, etc.) than conservative in-groups (white, wealthy, etc.). Then have a look at who is proposing politics intended to fix that imbalance an who's talking about "taking a hard(er) stance on crime".
Another, rather specific example: https://www.dailymail.co.uk/femail/article-8769269/Former-abortion-clinic-worker-recalls-pro-life-women-justify-procedures.html
Once you look our for the pattern, you'll see it everywhere.
I suspect similar to what we're already seeing in terms of "tuning kits" (solar thermic energy kits, decentralized power kits, new insulation...)
The main direction for improvements from an SP perspective would probably be in the realms of
increased efficiency of those kits
decreased production and maintenance requirements for those kits