I'm not someone who's generally in favour of the invasive regulation of particular sectors. There are cases where we might need regulatory oversight, like if we're allocating spectrum, but for most industries, I prefer to let competition policy do the work.
We need more information about the status of challenges in, say, the grocery sector. It's received a lot of attention because prices absolutely went up. There are a lot of reasons for that, and competition—or a lack of it—is only one proposed explanation out of many. Maybe it has a part to play, but we don't know how big a part.