is that really realistically or just a dream ?
Noone knows, this is just speculation. I doubt it will be that high so soon.
50 000$ maybe but not 500 000$. But this is my speculation, everyone have their own

Yes, today such sum looks unreal, but we can't know what future waits bitcoin and what price will be in 2030 year, with the same chance it can be 0$. Now we can only suppose and imagine.
There is a big question mark on what will happen to price of bitcoins in future as no one can predict what will happen in future either it can touch to the moon or even it can fall back to zero level but things are going smooth at a moment so we can expect the same thing in future as the demand will go higher which will help in taking price to higher level.