Is bitcoin needs some regulation to use widely and accepted by all countries ?
Yes. It may seem backwards because one of Bitcoin's biggest selling points is its decentralization and some people see it as an anti-government tool, but really, in the times we live in, no regulations means a free rein for scammers, and we've already seen criminals take advantage of it.
While most of the users now don't really need any protection, majority of the mainstream does. Look at Japan and how open their government is to Bitcoin. Their citizens feel that it's safe because they're able to enjoy their liberty with protection. No country is really emulating them thus far, but that's just one example of regulations actually empowering the Bitcoin and crypto market in general.