Generally, I'll remember it as the period when Golden State had its super team (despite their two losses in the Finals) and when the Celtics overachieved for three years. They never really had a chance at the title, but they made a couple exciting runs.
I'll also remember Boston's "blockbuster" free agent signings--Horford, Hayward, and Kemba--and how that was the first time in my decades as a fan that I can remember us landing big FAs.
Last, I'll likely remember our most recent season as the year that the Celtics imploded and had their "Kyrie year."