This question is almost rhetorical. Yes, competition drives innovation. When Ryzen APUs only had Intel to worry about, they rested on their laurels with stagnating but still superior performance. Intel did the same thing with 4c/8t desktop CPUs during the Bulldozer dark age.
SoCs are good for the segments they target but they're by no means the be-all-end-all of personal computing. The performance of discrete graphics cards simply can't be beaten, and desktop users want modularity and competitive perf/$. Framing the distinction between a highly integrated SoC-based computer and a traditional motherboard+AIB arrangement as a quantitative rather than a qualitative difference is an error.
Both Intel and AMD have already received Apple's wakeup call and have adjusted their strategies. I also think it's unfair to say that nothing has changed until just now. I consider Ryzen 6000 to be an understated milestone in this competition with a big uplift in iGP performance and a focus on efficiency. There's a wide gap to close, sure, but AMD and Intel have certainly not been standing still.
Apple's vertical integration and volume made them uniquely suited to produce products like the Mx line, so it makes sense that they were able to deliver a product like this first.
