To be fair, Steve Jobs acknowledged this in a 1990s interview:
"And they showed me, really, three things, but I was so blinded by the first one that I didn't even really see the other two. One of the things they showed me was object-oriented programming. They showed me that, but I didn't even see that. The other one they showed me was really a networked computer system. They had over 100 Alto computers all networked using email, etc., etc., but I didn't see that. I was so blinded by the first thing they showed me, which was the graphical user interface. I thought it was the best thing I've ever seen in my life."
Jobs would revisit object-oriented programming and networked computing when he started NeXT in 1985. NeXT is closer to the Smalltalk environment than the original Macintosh was, with its support for networking thanks to its 4.2BSD underpinnings and with its object-oriented APIs and programming environment, coded in Objective-C, which is essentially the Smalltalk object model on top of C.
There's another Xerox PARC-inspired technology that was a core part of the NeXT experience: Display PostScript, which was NeXTSTEP's foundation for rendering graphics. While PostScript is an Adobe product, Adobe was founded by the creators of Interpress, an earlier page description language that was a Xerox PARC project.
Steve Jobs definitely knew a good thing when he saw it :)
