How much longer do you think Playstation has? 

For as long as consoles remain a commercially-viable platform for playing video games. I don't see Sony exiting the console market any time soon. It's their biggest money-maker.

If they keep going like that, for a very long time.

more than the xbox I'm sure

The way they are going, each new console generation is all but guaranteed a success due to the previous one.
Even if they screw one up (which they did with the PS3's, but only for a portion of its lifetime), I think they'd need two major disappointments in a row for there to be a question of an exit from the business.

So I expect a PS7 at least.

At the moment, they're probably the most secure of Sony's businesses.

For many, PlayStation is synonymous with game consoles.

Hardware? Two more generations.

Brand (controlled by Sony)? I don't have the faintest idea.

I cant imagine hardware lasting many more gens by virtue of the fact that tech isnt advancing that much that fast, and even if it does I dont know if videogames will tap that power, very few games take full advantage of the PS5 capabilities.

Consoles till they want services to be the only possibilities and work on a TV/phone instead.

Peripherals that connect is a fair idea (reading commenter after me responding to another). But like Clank from R&C being cut for possibilities of animation/time I do wonder about that with multiple hardware. Sure not just hardware upgrades but just controllers of varying types, what games use them or just a regular, pro, third party and Keyboard & Mouse who knows. Whether like it is nowadays or other possibilities.

Either way I didn't think about peripherals too much but glad I read below it's a great point. But whether a PS tablet/phone/TV, who knows what hardware angle they choose to go with. Portable but powerful. Syncing between both dock or wifi/bluetooth in the future (however far data transfer can get in coming years).

If they keep with consoles sure but digital/physical and isn't only collector's editions or they ditch that side entirely and it's digital only artbooks/soundtracks and more via certain services not even the console anymore (why would they give away music files that easily even if DRMed XD).

However much we pay for resolutions via these services in the future like TV/movie streaming services, or other factors companies will come up with (as long as games don't get every interaction money greedy were fine).

Hardware though hmm, maybe PS6 that and it being digital only but we have to see how things go still for this gen for console sales or if they go nah we know physical sold more but eh we don't care and still push digital only.

I mean they have the PS6+ names but that doesn't mean much either. They could change each streaming service app to be PS7 for all we know and upgrade the new one then just changing the existing, sounds dumb and it is but just making wild ideas here no matter how dumb they are.

Depends what they plan/think will take off and react to it in response.

Will controllers change still hmm whatever they have planned I don't know yet. Will we get AR with PSVR3 (aka mixed reality headsets I mean by that) no idea even. Any re-introductions. Remote play is still a factor for Sony PSP, Vita, phones, PS Portal in.

Will PSVR3 be it's own system I doubt it regardless of how powerful they want things to orbit the PS5 so much Portal, PSVR2 headset, other services, even if a service can be separated from the console they still combine it as a middleware device, I do wonder if they will pull away from that gen to gen or not. Will Sony pull away from their hardware focus? I do wonder. I mean they still have phones, cameras, MP3 players. Will they want to save on physical and even bother with an 8K Blu-ray for the Blu-ray alliance of companies?

Xbox will pull away, TVs and phones have started, the streaming box has been shelved. Microsoft want services/software they easily skip hardware while Sony is more hardware focused so I do wonder.

Nintendo no idea they could do anything still family understandable of physical even for all we know for 2 more gens or forever.

The money sure but I think customer response/their thoughts on the matter to save money/transition or not.

I love consoles, gameplay, hardware to use it well forced or not.

But we can't deny the 'possibilities' either of the future and how they want to use the tech then how it 'should' be used.

To kind of follow up with that a bit:

I think we are soon approaching a point where we will have tech so advanced that there will no longer be a point for console upgrades.  There will be a single Playstation device where different peripherals can be added to it for different needs and the same with the other console brands.  Basically reaching a point where you just buy the console or consoles or your choice and use them until they finally wear out and just replace them as you need.  Console generations may last decades instead of just years.  

So the PS7 may be the last one, but they will continue to manufacture it forever, with only small changes.