Socal, you're comments on the cool Mediterranean climate are generally spot on, though you could argue that Bremerton and maybe Sequim- in the rain shadow of the Olympics- may also qualify, even though they are further north than Olympia. Certainly, my grandparents had no problems growing figs at the Byrmryna Fig orchard on Vashon island- located halfway between Seattle and Tacoma- during the 1930's, 40's and 50's, before the arrival of Starlings on the west coast wiped it out.
Your comments on coolness effecting development is also spot on. In my experience with 24 different types of citrus in Southwest Washington-- just across the Columbia River from Portland-- only lemons, limes and the earliest ripening Satsumas produce quality fruit before the weather turns cold in late October. Yuzus, Sudachis and Kabosus fully ripen in early November, just before the onset of the first hard freezes, although Sudachis actually have their best flavor picked green and used as limes just before they start to color, usually in late September-early October. Meyer's lemons ripen a couple-three weeks later, and need protection. Thomasville Citrangequats don't really ripen fully at all, though they do color up a bit, but again- like Sudachis- can be picked green and used as limes.
Of the Satsumas I've tried, only Early St Anne, LA early, Miho and Xie Shan have produced what I consider commercial or 'better than commercial' quality fruit, though the Xie Shan was a bit acid on a PT rootstock. Regrafting it to a Flying Dragon seems to have enhanced its sweetness, however. The standards like Owari or Brown's Select tended to be small sourish and mealy. I'm currently trying Okitsu and China S-6, but don't have enough info to make a judgment. Seto and Miyagawa should also do well.
Oranges don't do well, although surprisingly-or maybe not-, Kiyomi Tangor almost makes the cut.
Because the Puget Sound area has about 30% fewer growing degree days than SW Washington and the Williamette Valley, ripening in the Olympia area may not be quite so robust, except perhaps in sheltered microclimate, without artificial enhancement.