Sony home consoles never really die so soon. It's now been out for roughly 4 years, which judging from previous Sony consoles would give it at least another 4 or 5 before its discontinued, possibly even later. Don't see why people would expect the console to go away in the relatively near future.

I'm not expecting PS5 before 2020

It is not about how long PS4 will be on the market, people hear it as their will be no PS5 soon.

Even if PS5 is planned for 2019 they will still say this.

Edit: Playstation 5 before someone who thinks he is funny  PS5 Persona 5 already exist!!

Of course it will be here for many years. Even if PS5 came right now, at this very moment, it would be strange if PS4 wasn't here for at least a few years.

Good, we don’t need a PS5 before 2020.

I would be happy either way but I think since sales are higher then ever and there is so much possitive energy around the brand going for a 2020 release on ps5 seems logical.

Look how good graphics are on ps4 slim games shown at pgw. No need for ps5 until 2020 or 2021

We need 2 occurrences to happen so PS5 exist.

Performance leap... something that can be at least 10x better than PS4 (4x PS4Pro, which is small)
SW sales and HW starting to decrease for we to mark the release of the new console at about 2 years after it start declining.

Neither happened yet, so 3 years is almost the minimum for PS4.

Considering PS3 was far less successful, yet it’s still being sold brand new in most markets, isn’t this kindof obvious? Even if we see PS5 in 2020/ 2021 timeframe, there’s no reason why PS4 will suddenly die.

This is Sony so not only will the PS4 stay for many years but it'll be supported for many years a long with it.