After multiple trips to California and not yet seeing a sequoia grove (it’s always “too far”), I’m committed to getting a visit in on this next trip, in September. Looking at something like this over 4 nights, using SFO as the entry airport since I can burn United miles to that airport on nonstop flights.

Thursday: arrive SFO 9:15pm, drive south right away far enough to get away from Friday morning traffic.

Friday: Drive to Santa Barbara along the coast, never seen anything between Palo Alto and Zuma Beach so it’s all new. See what top things, or hike where, or just enjoy the view. And I know there are redwoods in this stretch, seen Muir Woods, camped at Jedidiah Smith SP, done redwoods already, I want to see the big trees.

Saturday: Wedding in Santa Barbara

Sunday: Drive to a sequoia grove, first thinking near Kernville (closest) but reading that these southern groves are in decline due to climate change, so maybe head to Sequoia NP and sleep there in the park.

Monday: Fly home from Fresno 4 pm flight (nonstop flights out of SFO @noon, probably too early to reach from Sequoia NP, or too late, a redeye that night, not interested).

Is that at all reasonable, or just too much distance for 4 days?

For sure drive Rt. 198 out of Visalia. See the General Sherman Tree and the visitor center. The other way out of Fresno is on a San Joaquin train to Sacramento or Oakland. SFO isn't the only airport in that area. Check on Oakland and Sacramento.
If it is just you and not a group, I'd stay at the Pigeon Point HI hostel about 40-50 miles south of SFO on Thursday night. The view on Friday morning will amaze you. Near Pigeon Point you can see some big Coast Redwoods at Butano State park.

Thanks, good suggestions.