You might think so, but it turns out it’s a completely separate issue. People began reporting problems with Alexa not triggering routines back in May as soon as the new Alexa skill began to be deployed, and SmartThings hadn’t done anything one way or another with echo speaks at that time.
New SmartThings Alexa skill (2020)
And it’s not Amazon restricting the functions, it’s smartthings deciding that echospeaks takes too many resources in the cloud. (just as an example, you can still use the original echospeaks with Hubitat, as the author of echospeaks has confirmed in the author thread in this forum.)
Again, all of this is discussed in detail in the announcement thread about the new Alexa skill. You can see there the dates when people began reporting the problems. 
It’s just that Smartthings decided to force the change over to the new Alexa Skill about the same time they cut support for echospeaks. So suddenly a lot more people were affected.