I immediately thought it was a glitch - or just an accidental poor UX.
If they got rid of like counts entirely I imagine people would start to leave the platform in hordes. I certainly wouldn’t use it. I use my IG for promoting my music and need to know how well each post is doing.
It removes the value proposition from the platform for me if I can’t tell how much people are engaging, or who. There’s literally no point for me otherwise.