Yes, Bitcoin has done well in the past and has blessed those who invested early in it, but are you sure you can attest to the same thing in the next 30 years? What I like people to know is that this is a speculation, it may work or not work, it's a risk on its own, whether we like it or not. Today's view doesn't count in the decades view, things can change.
I understand your skepticism but we only have a few years to look back at. Since its inception in 2009 bitcoin price in terms of fiat has been going upwards and not downwards. Keeping that in mind its price should keep continue growing in the next decade. Unless some drastic happens, which is again possible but a rare occasion.
Frankly, if someone plans wrongly with Bitcoin, such may pay dearly for it.
This I would agree with. I have seen users talk about leaving their job and selling their house for bitcoin. These are wrong steps to take and frankly these people lack the investment mindset if they are doing such things.