Well 3rd part games are not main thing that selling Switch on first place.

Talking about XB1 vs Switch in US, going buy Vgchartz numbers XB1 is currently at 22m in US, so what we can realistically expect LT, around 30m, no way it will hit 35m.
Switch will sell like 40-50% of its world wide sales in US, so if Switch just hit even 80m LT world wide, we talking around 30-40m in US alone.

I think when ps5 and xbox 2 come out switch will be slow down considerably.

It will all depend on when those rumored console release and how Nintendo can continue improving aspects of the Switch with either new models or something else.

Yeah, Switch will than definitely start failing of a cliff. :D

Joke aside, when PS5 and XB2 come out, Switch will still have two its main points for selling, Nintendo games and hybrid nature that PS5/XB2 probably will not have. So nothing really will change for Switch, especially because Switch will probably in that time period have price point of around $200 with already strong built in line up of games while PS5/XB2 will be $400+ consoles. You can look even current situation, PS4/XB1 dont effect on Switch sales and Switch sales dont effect on PS4/XB1 sales, same will be with PS5/XB2.

What are your PS4-forecasts for October?
The PS4 bundles of Red Dead Redemption 2 and Call of Duty are appeared. a incredible month, again.

yup i think RDR 2 will carry ps4 till next year then some. all other games will look like a joke next to it.

Current word is Black Ops IIII did very little to boost PS4 or Xbone.  Red Dead will do more.  Will be interesting to see how much, word is sales for October have thus far been run of the mill for all platforms.  The tracking tool has Switch leading the month with preorders for RDR2, Smash, and Diablo III bundles accounted for (all will fall in the NPD tracking period).

xbox one launched at a ridiculous 500$, i think that should be accounted for as well, i think only the extremely hardcore xbox fans would pay that much. 

$40 vs $60. More than double dollar sales. I'd wager it's closer to 1.5:1 in favor of PS4. But to say that platform had nothing to do with it is kinda weird. Of course the platform with the most JRPGs has JRPGs that sell very well. It's not a slam on Nintendo platforms, but rather that it's the place that makes the most sense. I imagine the Switch port if done well, should be successful too.