On what timeline were they late to develop it and announce it? Did someone at Canon tell you their internal timeline, and then Canon missed it? Or are you just basing this on rumors or your own expectations? Pretty sure that’s it. So no, they weren’t late.
Canon developed and announced it when they were ready to, and started shipping it when they said they would in the announcement (many people apparently received theirs, even before the stated date). How do you figure any of that is late?
Of course, none of that excuses their failure to provide adequate supply to meet demand. Still, this seems to be the new canon (little c) for Canon. For the most part, people who place a pre-order just after the announcement receive their camera/lens from the first shipment, which usually goes out on time. People who waited…will have to wait longer. In some cases much longer.