Implication(s) of “Though you wouldn't think it”

All of the above examples use the phrase though you wouldn't think it to denote that there is a disconnect between the qualities in the first clause from the qualities in the second clause. The critical word is though (or often, although).

In each case, the speaker is saying they are being characterized as positive, but they have done something that could, theoretically, bring into question that positive attribute.

The differences in the sentences are in the initial clause that gives a clue (but not necessarily a definitive statement) as to whether the speaker shares the view that they have the positive quality.

Some say is a phrase that distances the speaker from the message. It suggests doubt.

They are professionals is an unambiguous statement of the quality, and the reference to the disconnect merely points out the incorrectness of dismissing the quality based on the disconnect.

They are capable is identical in effect as they are professional. The speaker accepts the positive and acknowledges the (incorrect) negative.