I think game freak had switch dev kit by 2015 and started development on Pokemon switch games in 2015
https://www.gamnesia.com/news/the-pokemon-companys-ceo-wants-cloud-services-to-move-your-pokemon-across-g
>>32948793
That's good to know
Maybe 2018
>>32948793
And the switch SDK leak said copyright 2015
>>32948938
Definitely 2018
so that's why they didn't give a shit about S/M