Bitcoin, being the first and the most successful cryptocurrency, has being well adopted in many countries of the world which has reflected through its increasing marketcap and price that also proved it to be a well known deflationary currency.
Saying that Bitcoin is well adopted is a bit too generous, considering that you can't just go outside and spend it, and you have to specifically look online for the closest places that accept Bitcoin, and then spend potentially a lot of time getting there. And even online it's hard to spend it, because big platforms like ebay or Steam don't accept it.
Now, people can hold bitcoin in a way to do away with theft and central (governmental) manipulations.
In no way does Bitcoin solve the problem of theft. Not only it can be stolen physically, if you have a paper wallet, a seed phrase, a digital medium with an unencrypted wallet file, it can also be stolen digitally via hacks, phishing, malware, etc. For people with poor security practices, which is the majority of the population, Bitcoin theft is a far bigger threat than some bank theft.