The biggest threat to bitcoin is from within, groups trying to hijack its brand and its development, first already done and goes by the name of "Bitcoin Cash", the next is planned for a few months from now and goes by the name of "Bitcoin SegWit2X".
Governments and banks will embrace bitcoin because of its property, much like gold.
This forking business 'Bitcoin SegWit2x' or the next one after that will be the end of Bitcoin and cryptos. This idea of creating valueless forked versions of an intrinsically valueless and intangible 'coin' is dangerous and once the market catches on and the bubble bursts, no crypto will recover and go above $1 in my opinion. This idea of undermining currencies every couple of months will prove fatal.