I believe SOMA is less horror-y and generally more approachable than the other frictional games. It may be because it's a scifi story, like the other games you mentioned enjoying.

I used to hate horror games, but I realized I actually just hated bad horror games. SOMA is a good horror game. It has a compelling story, fantastic atmosphere and sound design, and the frictional games devs are great at balancing the suspenseful moments with more relaxed thoughtful moments. All of this makes getting through a stressful or scary bit of the game more worthwhile.

Like Ashtear said, the safe mode prevents the monsters in the few areas they patrol from 'getting' you, which I would say somewhat gets rid of some of the suspense. However, after you've been caught once and have to reload a checkpoint, they just become an annoyance so I wouldn't blame anyone for turning safe mode on.