asked Grok why I get so many replies from people who don't follow me. All a spam tactic if you ask me.

This is what Grok said:

For many of them it is a growth tactic, not random noise. Replies put their name in front of your audience. A comment under a post that already has attention is visible to people scrolling the thread, which is cheaper than trying to get their own original posts discovered. The algorithm also weights a reply far more heavily than a like, so the activity can help their future posts travel farther.

That is why small or new accounts do it on purpose: they borrow reach they have not earned yet. A useful reply under a bigger account can produce more profile visits than a week of posting to their own tiny following. Generic or copy-paste versions are just the low-effort version of the same idea.

The catch for them is that X has been trying to push stranger replies down the list and surface mutuals first, and obvious spam patterns get filtered or hidden. So the people who keep doing it either think the exposure is still worth it or they have not noticed the quality drop.

I hate to go back to NOT letting all reply but might have to.

Source: Sunrise Trader