Time out ( ~ 2yo)

My son is 21 mo old & our current time out routine has become very ineffective.

Shortly after his 1st birthday we started implementing the occasional “timeout”, I would take him to another room & hold him while counting out loud to 30, occasionally taking a break in counting to say things like “this is timeout, we are having time out because X, etc”. It was really effective because it worked as an extended redirect when normal redirects weren’t working, it removed him from the unwanted behavior long enough to actually move focus. As he’s gotten bigger it also gave an opportunity to talk about the behavior or action without as many distractions & it became a effective deterrent to behavior.. that is, “if you do X, you will have timeout” often was incentive enough to stop.

But lately it’s gone down hill... it’s no longer a deterrent to anything. I feel like at almost 2, it’s probably time to change up what it looks like (ie not me holding him while I count 🤷🏻‍♀️) but idk what it should look like. How do you do time out with your LO that is a similar age. Is it effective for them?