After applying jump boost 2 via a full beacon, the player can't jump up onto a two block high pillar. According to the wiki (and from past experience) I should be able to jump 2+ blocks high.
"The player can normally jump up a distance of 1 1⁄4 blocks. With Jump Boost I, that increases to 1 15⁄16 blocks, and with Jump Boost II, that increases to 2 1⁄2 blocks."
You have regeneration selected, not jump boost II