Bitcoin reaching those ammount once again would mean a big issue problem had been found and exploited, this wold be the end for bitcoin, since pretty sure altcoin would replace bitcoin once it start to crash.
Bitcoin is open source, which means that everyone can look into Bitcoin's code and verify if things are how they are described to be. If there would be a severe "security hole", then
it would have been noticed and exploited already. Another benefit of open source is that Bitcoin can be updated/improved if needed. That's why a lot people like Bitcoin. It's transparency is a major benefit for basically every person
It is not so with big projects
Indeed, Bitcoin is simply tiny in comparison with, say, Linux code base (which is depressively huge by now), but the holes are still found even in old versions, while security vulnerabilities are a common thing in newer versions. In this way, any project which is being actively developed and which is a bit more complicated than "Hello, world!" should be considered as not completely safe. Once, I used such a hole myself to get root access on a remote machine (it was mine but still), and the exploit was literally a couple of lines in Bash script language