The content of Classic is experienced very differently when there isn’t existing/established player infrastructure in place.
Starting out on a fresh server (especially HC) is a very different experience relative to the availability of gold…the availability of raw materials… The population of players playing together at a sub 60 level band and running dungeons.
Dungeons are experienced differently. Boosting isn’t a thing at launch on a fresh server at least initially. If boosting exists on HC Classic, it will take quite a while to establish if it ever does and carry significant risk.
Raiding is experienced differently on launch compared to an established server for many reasons - too many to go into in a single post.
A big reason HC Classic MC is going to be ‘exciting’ has little to do with the content of MC itself…and instead will revolve around how the content is experienced.
On regular Classic MC…the stakes for doing a Molten Core are very low because death means very little. If you can brute force your way through multiple boss fights even with several people dying thought the raid (including but not limited to really important tanks/healers) then it’s worth the trade off for gear.
By contrast on HC…I think you need a lot more dedicated prep across the entire raid group. You can’t afford to bring people who don’t come with a bunch of consumes farm. You can’t afford players that aren’t properly equipped. Even when you have those things…you’re probably going to have to outright stagger MC progression and gear acquisition by proceeding more slowly. Small things like not attempting Magmadar until you have at least two if not 3 tranq shots.
Early deaths at 60 will have far more weight.
If you survive to BWL and are progressing there - losing a raid geared 60 is a substantial loss to an individual player and the raid.
What makes HC appealing as a game form is ironically how simplistic the raids are. If it wasn’t as simple, predictable, and solved as it is…it’d be much to difficult as a game form to attract much appeal.
The new content in HC isnt the existing fabric of the game, it’s how players create new content with what’s already there.
A 5 man clearing LBRS or BRD may not be particularly interesting to watch on normal, but even 5 man dungeon content can be a compelling play through or watch when any death is the end for a character or potentially multiple characters.