What does "Switch to WMATIC or wrap your MATIC" mean?

MATIC (and ETH) are not ERC20 tokens, they are native tokens. Before we proceed we need to know the difference between native and ERC20 tokens.

The following article can prove to be useful: https://cardano-ledger.readthedocs.io/en/latest/explanations/features.html#:~:text=An%20important%20benefit%20of%20using,handling%20logic%20to%20track%20transactions.

In the background, when using MATIC/ETH for blockchain operations, they are wrapped (converted to ERC20 token) and afterwards used for the operation itself. In that regards, Kromatika's GASless contract cannot operate with native tokens, it only accepts ERC20 tokens. Note: this only applies when you trade MATIC to anything else;

Figure A

Figure A shows that the "From" sender is not the actual address, because it is executed by Biconomy.

Notice that there is also transaction fee existing. GASless does not mean feeless. Blockchain fees still exist and cannot be avoided, but they are being paid by Biconomy. For that service they charge same amount as the transaction fee denominated in output token.

The last transaction of 1.19 KROM is for the relayer.

The above transfer of 13.04 KROM is what the user actually gets

The other transfers are regular swap transfers that occur as in regular aggregate swap.