Are People Now Against "Time Out"s?

I have a 3 year old who is going through a phase of boundary-pushing. When he being really persistently naughty, he'll be made to sit on his stool in his room in eyesight of me (door open) for one or two minutes. He hates the time out and generally when warned he is approaching one, he'll correct course to avoid it, so we only use it a couple times a week (right now - it's only the past month or so we've used it at all, because of this phase he is in of really challenging authority and asserting himself).

It works pretty well and is clearly not abusive or traumatizing and it doesn't abandon him to his feelings. I'm not putting him on time-out kicking and screaming - when he is having a full blown epic meltdown, we sit and rock together in his chair until he is able to calm down. Time outs are for when he's thrown a toy in the house once... been told not to... twice... been warned next time is time out... throw number three and he's marched to his stool for a minute or two to contemplate his life choices, lol.

So I'm pretty confused to be seeing some of these articles and social media stuff being very anti-time out. I guess I can understand if it involved locking screaming kids alone in a room - a child who is emotionally out of control needs attendance and containment until they're calm. Or if it was used constantly or the only form of discipline. Usually my boy can comply just through reminders and a firm tone. But for Big Nos like hitting, kicking, pushing, making big messes on purpose, throwing big/hard objects indoors, hurting the dog etc... just a "no" is not sufficient, imo. The purpose of the time out as I see it is to kind of force him to stop and collect himself and get himself under better control, as well as to express my significant disapproval.

What's the deal with the anti time out stuff? What do people suggest be done with the boisterous kids who are hitting, smashing, etc? Not bad or angry kids, just active, limit-testing, passionate little people who want to express themselves, including their healthy aggression, and need grown ups to help them set limits on themselves and learn what is and is not acceptable behavior.