Correct. I remember a few years ago someone mentioned that LaFrentz had the record and I spent a while researching it to see if it is true. The "real" record is Mark Eaton in 1985, when he had 456 blocks and 0 three pointers. Someone like Klay Thompson had 325 combined in 2016 (276 threes, 48 blocks) for a little more balance. But as far as someone with at least 100 each, it has been LaFrentz. It's an interesting combo of skill sets that is super helpful to teams, because it's rare to get somebody that can protect the paint at an elite level AND space the floor.
Maybe Wemby or Chet smashes this thing to smithereens though.
James Harden came pretty close in 2018-19: 378 3-pointers + 58 blocks = 436. In Steph Curry's 400-3-pointer season in 2015-16, he drained 402 of them but only had 15 blocks (= 417).
Serge Ibaka had a start of career with massive #s of blocks (241, 242, 219 in seasons ending '12, '13, '14), before becoming a good 3-point shooter after that (77, 60, 124 and 107 in seasons ending '15, '16, '17, '18). Ibaka's 124 3s / 124 blocks in 2016-17 was at the time probably the highest single-season # for anyone who put up at least that number of 3s and
blocks. Beaten only two years later by Lopez in 2018-19, as you observe (187 + 179 = 366) and this year, where he's got 8 games and in theory could still top himself.
"big men who can shoot 3s" is a very recent innovation in basketball, I think.