I miss the days where I'd sneak in there with a friend, woefully under-leveled and under-specced for the challenges that await us.

It's all soloable now, the + icons are leftover from when it was hard.

Ive just been through and completed it on my trial-specced healer (with an added spammable) and it's been a blast! It's mildly challenging and interesting. I had to work out a strat to kill Shada with my low dps, but it was rewarding to finally complete. I wish they'd bring out more areas with a similar difficulty. Zos raised base health and dps recently so this should reflect the difficulty of new content.

Craglorn was the first zone added after release, it was deliberately made harder because it was designed for players who had completed their alliance, the main story and Coldharbour and because ZOS assumed that's what players would want. They also assumed that by that point everyone would be playing together with a group of people, in spite of the lack of grouping tools for overland maps, and so requiring a group for everything wouldn't be much of a problem.

It was changed years ago to tone down the difficulty because (in spite of repeated claims on the forum that the game needs to be harder) apparently very few people were actually doing it and many who did try were going in solo because for various reasons they didn't have a group to play with.

A lot of areas are still marked as group content but apparently even the delves and things can be done solo by high CP characters with the right gear.

Craglorn was ridiculously hard to do solo when it was released. In fact there were several puzzles that required more than one player to stand on pressure plates to open a door, or some similar mechanic that blocked solo players in quests. I still loved it lol, I spent way too long soloing what I could.

The worst part imo was that when zos made craglorn soloable, they also completely erased all quest progress for everyone and basically reset the zone. Imagine spending 30+ hours in a difficult af zone to complete it. Then zos does that lol.. To their credit it was much easier/possible to complete solo after that, but they did kind of crap on existing players time.

Bring back original Craglorn wasps.

Loved the challenge of the zone and what Zos did but removal of it was start of making overland content something you roll through without thinking

Craglorn was a good concept that was poorly executed never to be picked up again. Murkmire was originally planned to be an "adventure zone" just like Craglorn, but after the bad reception of Craglorn they scrapped those plans.
After the Wrothgar DLC ZOS had found their new way of doing things, dynamically scaling players to be the same level as the zone, which in One Tamriel they applied to the base game zones as well, which made Craglorn from a zone spanning all the veteran ranks from 1 to 14 into a slightly more challenging version of any other zone with elements clearly designed for groups.

I do think that ZOS should work on making a more difficult overland again, but the way they went about Craglorn wasn't the right one. Overland content should be designed with solo play in mind but offer actual challenges for optional rewards. These challenges should be able to be done solo, but also with a group. That way you can track your vertical progression by how you have improved at taking on these challenges solo, but as a group you can clear these even on a low level early on. Mechanics that require extra players or a tank don't make for a good challenge.