What I find annoying from Sonic is their billing process. I dislike that they foist a random router onto you and charge you $10 a month (and charge you if you want to return it). I also dislike that they force a landline on you and charge you another $10 on you. Who in 2019 needs a landline? What I find somewhat dishonest, is how the sell it. I get that most advertising is not supposed to reflect reality, but it's sort of strange that you get excited about ads that say and "1GBPS internet at $40 a month" and only a year later realize that you're paying $75 a month instead. And that's something that's public, who knows what else about their business is as deceptive.
I suppose that's why Sonic has survived. I suppose that's the kind of business you need to run if you want to have a successful ISP.