You're right mate.I think your being a bit harsh, mostly it's because a fair amount of shows aren't slow but just irrelevant and boring. You could say Walking Dead was slow. I'd just say it was crap because nothing happened for vast stretches. I'm OK with this show atm because it feels like it's leading to something, the investigation needs to become more relevant to the premise of why they're there and what for, otherwise it will start to feel like it's not worth the effort.
All we are being shown right now are a lot of seemingly random things with nothing obvious to connect them.
TWD would blow their budget on 1st and last eps of a season with filler in between.
Lost was just weird unconnected happenings with a new strange thing each week.
Maybe "Silo" is not for the weak?