You can buy the GLD ETF at whatever fraction you want, and this is all done on the Internet. But sure, if you don't like gold, there are millions of other investments you can try (and you can buy REIT shares if you want to expose yourself to real estate, for instance).
But, are these as flexible as Bitcoin? Bitcoin is really the investment of the layman. They don't need to sign any documents, nor trust any financial institutions. Just create a wallet, and have coins sent to it.
Lots and lots of investors have been burned throughout the years by being convinced, "it will never go down" when discussing their favorite thing to invest in. I guess all I could say is, be careful with that, and keep a diverse portfolio. No financial instrument is "invulnerable".
By "invulnerable", I don't mean "always going up". I mean that it does not come with the aforementioned drawbacks of gold, stocks, real estate etc. That's why I consider it superior in terms of an instrument to put your savings to.