Right now it is not the block size that needs to be increased. It is the tx fees that need to be increased!
If you increase transaction fees you decrease the number of transactions, so you don't increase the total level of transaction fees.
By increasing the blocksize there is more transaction with constant transactions fees => total level of transaction fees increases.
But with your logic reasoning, the plebs can use Bitcoin as well. No, one must limit the block size so in the end only banks can afford to use it. If you like to make cheap transactions, please use one of the many centralized options available.
Not sure if serious.