You are right on the card having X2 weakness. It is because nearly all Hoenn and early Sinnoh cards regularly don't have the "X2" indicator as well as a level next to its name. This was a simple fixed in later Sinnoh expansions. I expect that they added it to the TCG to be more competitive and to avoid confusion like what you display in your question.
To avoid any further confusion or didn't answer it completely, I can revise my answer.