Depends on what are you reading, really. If the scene is needed in the script, go for it. It can help, and of course its not forbidden because, well, humans have sex (among other NSFW activities) so its an important thing to don't leave out just to appear nice and safe.
BUT if its overused, as any other resource, its just fanservice, unneeded, and unuseful. The other day I happened to see a BL graphic novel that had a lot of work on it. Nice drawings, colors, the script on the drama part was nice, but the dude -who was new in the neighbourhood- had in 3 days sex like 5 times, and masturbated himself between those times, and I was like -is this porn, or a drama/slice of life? It seemed to me that playing at having it all leave you with nothing in the end.
Maybe if I kept reading all have sense, but the mix was like screaming to me 'buy me for more sex, and maybe a nice drama thing'.