The answer to that question is: Yes
All previous releases of any software (Microsoft Windows in this scenario), will eventually become "hackable" by hackers out there.
Let's take this example: If you use a computer that has Windows XP, it is very very VERY insecure to use that operating system now. Microsoft no longer releases any security updates for XP anymore, because it is ancient software. No one should use that operating system anymore, even if they have a 3rd party virus scanner / firewall. It is still very insecure. It's a goner.
The same applies to previous versions of this current operating system. Technology has become so complex these days, that Windows 10 v1607 is practically a different operating system than Windows 10 v1909, even though it looks exactly the same. The system's important files are always being upgraded/updated by Microsoft. (I still use v1903, but it's still very recent, not too old) (Here's a small hint that's useful to know, if you don't already know: "1909" The first two numbers, "19", is the year (2019), and the next two numbers are the month "09", 09 is September. So the version of Windows 10 v1607 you have is July 2016. That's more than 3 years old!) Technology is always advancing so quickly, that, as of today, it is most secure to update to the most recent versions of releases, hence why companies release so many updates all the time that they want you to upgrade.
But also be aware, notice how I still have the previous version 1903 (March 2019)? The reason why I still didn't upgrade is that at this moment in time, Windows Update says it is optional to upgrade to that version. I am waiting until it is required to upgrade, when it automatically installs it. Reason why is because there may be some bugs/incompatibilities at this moment in time, but when Windows Update automatically installs it, then it is very likely that all the bugs/incompatibilities have been fixed.
Hope my post is useful for you to decide what you want to do.