as we know right now. saving bitcoin in last 2 years are very good than saving on the banks, but if you want to save it on bitcoin, you should check about how to save it, you should use a hardware wallet, because it will more save than you use a software wallet.
An advice, dont put all of your money in bitcoin, maybe someday you need emergency cash in real life
Don't go all in or else you would be fucked up and its hard to deny that we do still need fiat savings on day to day basis since adoption isn't still accepted globally
and also majority of us do sees bitcoin as an investment rather than a currency so its no surprise that people would be saving it up and accumulate while they can.
Why would choose between two if you can both save up bitcoin and cash at the same time? Balance everything and you should be fine.