This means the protocol can accommodate an increase of an extra 53-58% in txs (and that includes dust and spam txs like the ones we have now).
This is faulty thinking. We will start to experience serious issues well before 100% and user experience issues even before that. Already several times we have had two full blocks in a row and possibly other times more that I don't recall.
It is not enough that transactions occur eventually, they should also happen in a timely manner.
My postal service has at least 3 different speeds. A priority, B priority and express. And I can also use private courier for even faster. So 4 types of fees for 4 different delivery speeds.
If I don't care about the speed, I'll go second priority. If I do, I'll pay the premium. It's that simple.
There's no entitlement that I can produce all kind of spam and they have to be included in one or a few blocks (for peanuts).
You pay the fee, you are in. In a timely manner.