There is so much variation between the individual locations within each category, it's impossible to generalize.
The key thing is to understand why an area is less popular and decide if you're okay with that reason, and why an area is more popular, and be okay with not having that.
I personally live in both an HCOL and an LCOL region. I have a small condo downtown in a major city for access to healthcare and other amenities when needed, and I have an absolutely dirt cheap detached home in an LCOL region that I actually prefer most of the time. The LCOL region is unpopular because the medical access sucks, it's very remote, there are no jobs, and the weather the majority of the year is atrocious. The medical access is the primary reason I maintain the condo though, the rest of it doesn't bother me.
I prefer the LCOL region because the culture and nature are spectacular, really, truly spectacular. I live in a tiny fishing village of about 170 people next to a larger fishing village of around 2000 people. It has a hospital, but, like, barely, and I have complex health issues, so that's tricky. But other than that, it has everything I need. It's LCOL, but it's not a poor community, it's one of the wealthiest communities in the region, and there's A LOT there. It's a major international tourist destination, so a lot of money comes into the little system.
A nearby fishing village has no tourism and has virtually none of the amenities my village has. Their housing is even cheaper, but I wouldn't consider it a deal because of just how little there is there and how poor the average resident is. In our region, my village is the VHCOL area, so it's all relative.
I also managed to buy an extremely inexpensive condo in my HCOL city, again, because I understood the reasons for a specific building being so cheap, and I was okay with them. Within my HCOL region, my particular spot is extremely LCOL, again, relatively.
It's all about figuring out what's most important to you, and getting creative about how to meet those needs and wants. If you can find a specific feature that makes an area LCOL that you really don't mind, but everyone else avoids??? Jackpot.
I don't mind living out in the remote fishing village with no professional jobs, horrific weather half the year, and poor access to healthcare, because I work remotely, weather in my HCOL city is pretty atrocious, and I can get healthcare there.
By being okay with the downsides, I was able to buy an ocean-front, 3 bedroom detached home for 86K. ETA: I bought my condo just 2 years before for 142K, so even combined, and even spending 50K on repairs and an addition, my housing is still under 300K and absolutely dirt cheap for Canada. For perspective, a 600 sqft 1 bedroom condo about 5 minutes away is 630K.