Except one crucial difference.
The strongest point of Bitcoin is its decentralization and this is why the scaling debate is such a big issue.
Why is it that we're now ok with centralization ? If lightning leads to a few centralized hubs then we need
to design it in such a way that this won't cause issues further down the road.
We're taking this too lightly.
I can spin up a lightning daemon on one of my existing web servers quite quickly. And I could add bitcoind to it easily if it wasn't already on a particular machine. The barriers to entry are low. The cost on an existing server is negligible, but it can bring in revenue. It may be that this increases the number of bitcoin nodes because of this.
Very likely the numbers will be higher than the existing number of mining pools since p2pool hasn't been getting much love. Centralized mining is a huge concern.