No, you cannot be a fellow nerd. I am not sure if it is different for other spellcasters but even Bards apparently don't like quiet nights with a book. Though you can have a nice conversation about Tara in the follow up. What bothers me in the brothel is that he doesn't have even fitting replies to all that, which he is usually allowed to have, even if you fail that persuasion role he is still nice.
I was so sad I couldn't share the same interests as Gale in that moment, and I honestly didn't think at the time whether classes could effect your answers or not in that situation, but I guess it's a good it doesn't since I'm a Ranger and not a Wizard or anything. But yes the conversation about Tara was really sweet. (I really do hope they add more supportive options in general, as it would be so lovely as you said. Plus being able to share his interests would be amazing too, as I have a lot in common with him irl)
But wow I can't believe that Gale isn't even given the chance to properly respond, (like wtf?) I mean first he's feelings aren't considered or taken seriously, and then he isn't allowed to properly/fully express his feelings and issues about the situation? that's just seriously messed up, and honestly disgusting of Larian. The characters always get to respond to different situations, with different lines, so why not in that situation too. I know I'll never have any involvement in Sharess’ Caress myself, but It's so disheartening and appalling to know that it's in the game and that Larian treats him with such little to no respect, (especially since people already make fun of Gale in general) I really hope they seriously fix it soon. But I'm at least glad to see that some people are bringing light to the situation and defending Gale, so thanks for bring the issues up, as I would never have encountered that issue myself, as more people need to hear about it, as it addresses broader issues as well.