7 tps is ridiculously small. Only 604.800 txs per day. It was always a temporary limit.
Bitcoin probably already does far more than 7tps today if you take into account off-chain services in the market today( changetip/coinbase/exchanges/etc..).
It is almost certain that Lightning will take over all shopping txns once it is implemented, simply because it is cheaper and offers instant confirmation.
Although off-chain txs just move the centralisation elsewhere
Its important to consider what is being centralised.
-Centralising mining/validation centralises control over the protocol itself, meaning everything is subject to change (money supply, censorship, etc..). Getting this wrong will destroy the currency.
-Centralising transaction processing over a trustless system like lightning only allows a hub to lockup your money for x amount of time. They can never steal it or touch the protocol. Choosing a bad hub will lock up your money for X blocks depending on what X you chose.
Also id like to add, that the grand vision for lightning is to have a decentralised hub network like mining is today, meaning your wallet will automatically query the list of lightning hubs out there and choose one based on your cost preferences/configuration. Similar to how packet routing works today for the internet, your wallet will find the most cost efficient hub route to your payee.