Right, but a professional what? Different professions dress differently. You don't see many professional soldiers going into combat wearing ties, for example.
Seems your company president wants you all to think and act like people who naturally wear ties, i.e. businessmen like himself; which is all very well, but it would be nice if he could do so without suggesting that the rest of us do not have every right to be considered professional based on the quality of our work and our dedication to it, rather than on whether we tie bits of brightly-coloured cloth round our necks or not.