Maybe it is more than an instance. Maybe it is an idea, a world-historical vanguard, light itself. 
actual attempt to answer (cringe)
We’ve been around for three years on a lemmy fork before federation. The lack of federation for years as well as the place we splintered off from (/r/chapotraphouse) already having a unique microculture within Reddit has given this instance, in my opinion, a distinct culture compared to general-purpose and even other hobbyist instances.
Regarding specifics, Hexbear is a vehemently queer-friendly/intersectional anti-sectarian socialist instance. Check us out 
At the risk of posting crime on main I kinda missed out on the time between rhe sub and federation but there was nothing on reddit half as good as the sub since and it's legitimately good to be back amongst people who will yell at me fo what 99% of the population would consider an inane opinion.