Well, if you argue that way, I honestly do not think there has ever been - or will ever be - a good moment to buy a certain product from any product line Apple offers. This holds true also for any other similar tech company.
Progress just cannot predicted - sometimes the tech companies try to establish a certain new thing within a year and succeed, sometimes it takes years or even decades until they succeed, or it ends without a successful outcome.
Rest assured: as soon as you buy any tech product, you immediately and surely expose yourself to the risk of the product being outdated in a short period of time. This holds true to any product at any time, no matter what analysts say (and whose interests are behind certain leaks).
So, my recommendation would be to just not care too much. If you like what is being offered, buy it - otherwise leave it.
No one will ever be able to forecast when exactly it will be outdated, not even someone from within the inner circles of Apple Management (because even they don't know if their plan for the next years will succeed).