Regardless of the genre, I think you should a) write what the story and its characters need and b) what you're comfortable with. I write all genres, including BL/LGBTQ+, and I don't think one is any different from another. Just characters doing their thing in their world. And descriptive sexual content isn't needed unless it's actually part of the story or character development (like, there's something that happens during sex you need to show). We get hung up on sex, but this applies to anything. Nothing is really needed in any story if it doesn't further character growth and plot. Having said that, if you get to the point where you want to write it, there's nothing wrong with that either. I've heard there are BL readers that might complain when there's no NSFW (I've never had that problem), but there are also a lot of voices against NSFW (I've heard more of this, honestly). Don't listen to either group and just write the story you want to write.
I have a BL novel that has NSFW (soft, and only 6 scenes out of 120 episodes). There are some other intimate but not "mature" moments and some fade to black. I include sexual content because the MC suffers trauma from abuse and it shows how the two handle intimacy, how their relationship changes, and how they change as people. How they act and interact during sex is part of their character development, so I personally felt it necessary. And it isn't all "skipable smut" - stuff happens in those scenes. ^^
I have another same-sex light novel (male-male that started tagged as BL but I had difficulty picking a genre lol) that has no mature content. It actually had the most interaction out of anything I've written and I never had a single person complain or even mention NSFW. But it was more of a love story than a romance, if that makes sense? There was also friendship and found family and personal struggles that were just as important as the romance between MC and ML. Even though I changed the genres, at least 95% of my readers are BL readers.
I am working on another BL that has multiple NSFW scenes early on because it's a f*buddies to love story. I want to finish it because I like it, but I'm not sure about publishing for a similar reason. The relationship starts as purely sexual, but as it develops, it becomes more intimate, more emotional. Character development and all that. Sex is no longer the driving force, so the NSFW scenes will disappear to basically nada or short moments then fade to black. Not because they aren't having sex, but because it isn't important to show. So... I imagine many readers won't like that. They'll either not read at all because there's NSFW and they'll never get to the rest of the story or they'll start reading and like the NSFW and then be disappointed when it goes away. >.<
Sorry this was so long... I always tell myself I won't get wrapped up in these BL and sex-in-novels discussions and I end up here anyway.
TL;DR - I never write for an audience. I get a character or story in my head and I write it down. Sometimes it fits a genre, sometimes it doesn't. If I get readers, great, if they like it, even better, but if not... Oh well. Write what you want, the way you want. It's your story and your characters and you know best what they need.
