My arguement is that going forward most games are going to get a Switch version.  You are countering that by saying that Switch already is goetting a lot of releases.  Your arguement is actually proving my point, not contradicting it.

FYI, here is a list of the top 30 games this week from Famitsu.
https://www.perfectly-nintendo.com/japan-famitsu-sales-for-week-28-2019-july-8th-july-14th/

In the top 30, you get this distribution of games:

NSW - 20
PS4 - 9
3DS - 1

If you break them down by first and third party, then it looks like this:

NSW, 1st - 11
NSW, 3rd - 9
PS4, 1st - 2
PS4, 3rd - 7
3DS, 1st - 1

There are 9 Switch third party games in the top 30, while the PS4 only has 7.  That means that third party companies are better off releasing their games on the Switch right now.  Some might be Switch exclusives and some might get a release on both Switch and PS4.  Either way, these third party companies are benefiting from releasing on Switch right now.  I say this because the install base for PS4 and Switch are roughly the same in Japan and there are 11 Switch first party games on the list.  In spite of all of this, there are still more Switch third party titles on the list than PS4 third party titles.

Going forward, Switch install base is going to shoot far ahead of PS4 in Japan.  Why wouldn't Japanese companies want their games on the Switch?  Of course they would!  There should be no reason to doubt.  Over the next few years expect 90%+ of Japanese games to get a version on the Switch.  Switch is by far the dominant platform and third party games are already selling well.

Well I mean a sales comparison makes a bit more sense. I will do a quick one. All figures are rough estimates and may include minor errors.

2017 Switch MC 500

81% Nintendo 5.9m 19% Other 1.4m = 7.3m

2018 Switch Famitsu 100

79% Nintendo 16.6m 21% Other 4.3m = 20.9m

1st half 2019 Switch Famitsu 100

68% Nintendo 3.5m 32% Other 1.6m=  5.1m

2017 PS4 MC 500

17% Sony 1.7m (including CoD and Minecraft figures...) 83% Other 8.3m = 10.0m

2018 PS4 famitsu 100

14% Sony  1.0m (including CoD and Minecraft figures...) 86% Other 6.3m = 7.3m

1st half 2019 PS4 famitsu 100

11% Sony 430k (including CoD) 89% Other 3.56m = 4m

More notes: via hiska-kun

PS4 - 43 third party games of 47, which 32 of them were new releases
NSW - 28 third party games of 47, which 14 of them were new releases

While it may seem Sony has a decent chunk of the pie, it is only because they publish Minecraft and CoD in Japan. Nintendo on the other hand does not publish Minecraft so it is not included in their first party sales automatically. The PS4 is still selling more than double the 3rd party games as the Switch despite the equal/lower install base.

On another note, so far in Japan for Switch, 3rd party games have only sold 7.3m copies in 2 years and some months (8.3m install base), making it a less than 1 third party game per console attach ratio. But of course we are missing quite a few games due to Media Create quitting.

The 1st half of 2019 doesn't really show a trend since everyone knows that Pokemon is coming out in the 2nd half of 2019 to keep the ratio close to 80% with Nintendo. Hopefully the 3rd parties can match the year before or exceed it.

This is a pretty terrible conclusion, since the Switch only recently passed the PS4.  In 2017, the PS4 would have had an install base many times greater.  The part I bolded is a garbage statement.  

More importantly, I am not sure what point you are trying to prove.  Let me state the point I am trying to prove in case you aren't clear.  "For the next few years 90% of Japanese games are going to be on the Switch."  Did you disprove this?  Do you even disagree with this?  I am also answering a remark someone made that "third party games haven't proven to sell well on the Switch yet."  Do you agree or disagree with this statement?

I am just providing data as I apt to do.

You say 2 important statements. "That means that third party companies are better off releasing their games on the Switch right now" and "For the next few years 90% of Japanese games are going to be on the Switch."

The first statement suggests that 3rd party companies should release their games on the Switch and not the PS4. If that was not your intention then my bad, but that is what it seems, especially with the comparison with the PS4.

The 2nd statement is very vague, so it is not a statement that can be contested.

In 2017 the install base difference showed as the PS4 beat the Switch in SW sales. In 2018 the Switch easily beat the PS4 in SW sales in the top 100 with a lower install base. And again in H1 2019. But 3rd party games still aren't selling as well as on the PS4.