I really like the base game of Splatoon 2, but I skipped the DLC as it seemed to be based on high challenge I really don't like hard stuff as I play games to relax, unwind, and relieve stress, and these days especially I am in no mood to be frustrated.

Was recently wondering if it's worth picking up now, or whether my instinct to skip it was probably right?

lol, Octo Expansion isn't that hard

IDK, I only do multiplayer

Never even bothered to beat story mode and I'm playing those for almost 200 hours already

I'd say it's worth it. There are definitely some difficult missions in there, but the thing is you don't have to 100% complete it, you can go completely out of order and skip missions. If you get frustrated with one, you can easily skip it and move to another. The ending of Octo Expansion is amazing and worth anything though honestly.

Also worth noting that most of it isn't THAT hard. A bit more so than the campaign included in the game, but other than some specific missions I didn't think it was crazy tough or anything.

I actually didn’t play the single player campaign included, but did buy and beat the expansion. Honestly don’t remember much other than you get a special gun that really isn’t that special, imo.

I have 600+ hours logged on the game and it’s a safe skip for me.

It's harder than the main campaign, but it's not superhard. Most levels are not all that difficult. You also don't have to complete every level, and if you die too many times there's a skip level function.

Yeah I was relieved to hear you could skip levels you got stuck on, but even then, I wouldn't be having much fun if I spent the whole time failing and skipping, failing and skipping.

I'm not the most capable gamer due to mild motor control impairment. I can still play most games just fine, but my fingers aren't fast or accurate enough for me to ever be an expert gamer, and I get pissed off easily when I fail at stuff.

About the hardest games I've ever beaten were Monster Hunter 3 and RE4 on Professional.

I didnt buy it because I didnt enjoy the single player mode. Only the online multiplayer.

I should probably state for the record that I played and highly enjoyed the game's day 1/non-DLC campaign.

It's hard to compare it. RE4 on professional is probably harder overall (assuming you're not carrying over a save file with weapons and such), but a lot of the challenge in that game can be mitigated by good planning and resource management, where here the challenge is mostly about reflexes.

The best comparison I could think of is that the jump in difficulty from the main campaign is similar to the jump between Mario Galaxy 1 and 2. It's notably harder, but still not crazy hard.