OK. I’m back. Let’s try.
Yes. Conversing with someone of the opposite gender is sinful, according to Halacha, actually a well known Mishna in Pirkei Avos. And the Rambam states to distance oneself from women “EXTREMELY, EXTREMELY” (if my memory is not failing). So too advises Shlomo Hamelech. I have a hunch that he was slightly smarter than some anonymous entity who claims he has it all figured out.
Actually they did that in the era of the Mabul (great flood). Only they went a step further – they actually ‘tried out’ all the females they encountered, מכל אשר בחרו, to “be able to conquer that taiva”, I suppose. (and by the way, modern day society isn’t lagging to far…)
And to answer another question of yours, YES, a gay person is a sinner, no matter how cultured he is. We have our set of morals, ideals, lifestyle directly from HaSHem. He says explicitly in His Torah ואת זכר לא תשכב… And ואיש אשר ישכב את זכר..מות יומתו. His Torah is the absolute truth, whether we understand or not. In time of Sanhedrin he’d be put to death, notwithstanding that he feels he’s leading a so called moral life. Hey who’s calling the shots here? HaShem says his lifestyle is a תועבה, and he has a gall to call himself moral?!? HaShem deemed it an unnatural lust, and he legitimizes it?!?
And back to the Rambam (it’s Gemarah and Mishna too), he tells us to be in the environs of Torah true Jews. In the company of Torah practicing Jews – BECAUSE WE ARE SO AFFECTED BY OUR SURRONDINGS, our friends, our neighbors.