Getting all named characters to 50/65, 15-20-25m gold in the bank and >500 3* orbs of desired types is absolutely worth the grind in my book.
This, 100%.
Considering my recent luck, I find it way more fulfilling to spend time/mythril grinding something guaranteed (levels, 3* orbs) than dump mythril into the gacha. At least with honing abilities and getting my roster level-capped I can see the finish line. (Until new characters and abilities come out, but still)
This event is a good opportunity for grinders and gacha pullers though so everyone wins.