Ending 23 years ago (and saying "12 years" is grossly overgenerous). Of zero relevance to the modern Apple computers (edit: Sorry, it isn't even called Apple Computers anymore)
No it isn't. 23 years ago Woz was a "motivational factor" at Apple for the preceding 4 years. The prior two+ years he was off after an accident. Before that he worked with Jobs for 4 years.
His real contribution to Apple was for four years of the company's 34 year history.
I have a feeling that those were by far the four most formative years for the company, and that his impact on the company's identity and so on was probably comparable to anyone other than Jobs's.
If nothing else, he created the expectation that superhuman technical feats would be performed on a daily basis, which exists to this day, and might well have stayed true to some degree even during the between-Jobs years, even if said feats were not in particularly productive directions.