A Raspberry Pi is extreme, but again, I’m not talking about a few block size doublings. “Visa scale” is on the order of 1000x Bitcoin’s current capacity.

The other argument I’m familiar with is longer block propagation times lead to more orphan blocks, which is a centralization pressure.

EDIT: responding to your edits:

> layer 2 payment solution which essentially will force transactions to route through centralized middlemen

1. Layer 2 solutions aren’t necessarily centralized

2. Even if they are all centralized I don’t believe it’s worth sacrificing decentralization in the base layer to support small payments