The one advantage Apple has in being forced to do virtual events is they can tailor events to specific products and have as many as they want.
So there is no reason for Apple to not do a separate Apple Silicon Mac event later this month or early in November to coincide with the launch of macOS 11. This would then give them all the time they need to really hype the first Apple Silicon Mac and how future ASi SoCs and GPUs will allow Apple to advance Mac hardware in ways Intel/AMD would not allow them to.
While I understand this logic, there are a few things to consider from a marketing standpoint.
For one, there is a strategy to picking the right time to release a product. In the US, it is election season, and there have been studies that show consumers awareness of new products goes down considerably around election time. That means late October and early November are very bad times to announce new products because you risk election news taking over, and people forgetting about the new products.
You also don’t want to hold events too close together as well. You risk one event getting overshadowed by another event. It’s actually better to have one longer event in one month than two shorter events in one month because the press articles will cover all of the products in one single article, rather than having the product be overshadowed by another a few weeks later.
That is why Apple has never held two events in the same month. They want to give at least a month for the news cycle to talk about their products. After about a month media outlets have moved on to the next thing, which is when you hold your next event.
Of course the holidays play a big part of that too, and Black Friday sales (even though Apple doesn’t partake) are still a factor as well. If people are already in a “Christmas shopping” mindset and they know about a new Apple product that was just announced, they’ll buy it (or at least wait to by that product instead of something else they see at the store).
There’s also looking at other tech companies and not wanting to hold an event at the same time - though it doesn’t always work.
So apples marketing team still has to factor in a ton of variables (even more than I have mentioned here) in order to make the biggest splash. That’s why October 13 was the perfect date. It was far enough away from the September event to allow those products time to shine, but it also isn’t too close to the election that it will get swallowed up by election news. The next event date I could possibly see is late November, but that’s too late to get shipments to stores before Black Friday. So it’s actually possible Apple could have a jam-packed 2-hour event on October.