Malec deserves intimate scenes. BUT the scenes we get between them leading up to them having sex offscreen were all amazing, furthered their story, and were emotionally intimate. Even in 2x08, we had some nice moments between them, and Alec standing up to Maryse about him and Magnus being together was really important in their development as well.
Collectively they’ve had more “couple”scenes than Clace or Climon. So I think the writers DO care about them. But I don’t get why it’d be so hard to include a small scene of the two of them the morning after, or something. Anything. So yes, they do deserve better, but they’ve also been given a lot of good things too.