September 2018 was too soon. But the system is still selling at $299 (slim) and $399 (pro).

But from now It all depends on Sony’s strategy, do they want to make the most profit possible or want to sell more units??

where are now all those people who said 10M total for the PS4 this year and 3M total for XB1 ???
where!?!?!?
and the how bad will the PS4 drop with the PS3 examples.. I am laughing
just like PS1 and PS2 did in their latest year, the chances are now getting bigger for the PS4 to do the same.. if not better, and is doing it at 300$ now.
And we still have big games to come out for it until the year end .. so one drop last year from 18M to 14M and that was it, this year has to be around the same or 1-2M drop at max. What were those 30-40% you talked about ? where are they ? just like ps1 and ps2 had some years with little to no drops in their last years, now is PS4 turn to have years like these .. one drop per 2/3 years. And if Sony are smart they can help it.. they can make 50 to 100$ price drop at let's say september, and in 2022 or 2023 again to maintain good level of sales just like PS2 and PS1 were, and there you go, PS4 can reach very very good numbers LT maybe around 140-150M if it continues to sell at a good for it's years level just like this and last year (because 14M for console in its 6th and 7th year is just awesome) and even if they didn't do pricecuts (just like PS3) PS4 is now doing around double the sales of the PS3 in its 7th year, so even without pricecuts PS4 still should reach at least 135-140M, if we put around 13-14M for this year - this is 120M for this year and I don't believe it will have big drops, however let's make haters's scenario - so let put next year at around 8-10M, so we are at 128-130M with 2021, the at least 4-5M with 2022, and 2-3m more for maybe last year - 2023 this is around 138M lifetime, and this is in worst case scenario with big drops - around 50% per year, which PS console don't do ( the PS3 is the only exception, however this console was selling way worse in it's life than PS4, and PS4 will die way better )

All of this is without any pricecuts, and I think this is preety realistic prediction to even the haters around here.

As for the xbox one I can see there is possibility for it to reach 55M with good marketing for the next 2-3 years and permanent pricecuts. ( because this year xbox one is getting to 50M like it or not, and for the next 2-3 years that will be on the market it is preety realistic it can make another 5M. )

No one predicted a global pandemic 

PS4 Europe numbers 6 months away from being replaced by PS5 are just insane. PS4 is still selling like it's at the top of its game in Europe and easily outselling the Switch which is actually in its prime. Europe is the reason why the Switch won't ultimately pass PS4 lifetime and will probably end up like 10+ million short. PS4 has been dying in japan for a while, getting weak in America, but still crazy strong in Europe. Sony dominates Europe in the way that Nintendo dominates Japan, but Europe is a much larger market.

Well some predicted cataclism in 2018 or even 2019 predicting PS4 wouldn't pass Wii =p