Mainly, it's been something I can watch with my dad (for whom F1 took on its significance back when the cars were incredibly dangerous, and the racing very close).
It does become a different beast when you have someone to support, though - you're willing them to manage an overtake, feeling the tension when they're trying to fend off a rival, facepalming when they crash or the car breaks down, cheering them on if they manage some ridiculous maneuvre or exceed your expectations.
If you don't have a driver or team you're invested in (or if they're having a very bad season), then yeah, it does get very dull. There's always the thrill of ridiculous speed, and appreciation of the extraordinary sophistication of the engineering, but that doesn't necessarily carry you through moment to moment. I often skip races, and only watch unedited broadcasts for the season openers and closers.
Anyway, some seasons are better than others, due to the constantly changing rules, and fortunes of the teams and drivers. This year there's been a lot of overtaking throughout the field, and a VERY close rivalry for the championship, with lots of drama between two former friends. The only thing that's been missing is multiple teams challenging for the #1 spot, but it's been gratifying watching Ferrari fall on its arse, ozzie Ricciardo smacking down four-time champ teammate Vettel, '90s hero team Williams pulling out of a decade-long slump, and Hamilton finally clinching a second championship that's been a long time coming.
