https://devguide.python.org/#status-of-python-branches
Each Python version is supported for 5 years. So if you start building on Python 3.6 you are guaranteed to have a supported version till 2021. Upgrade to 3.7 (due out in June) when released and you'll be set till 2023.
So yes, Python does offer free LTS.
This is just Oracle being Oracle and finding another way to fleece their Customers, many of which were Customers of Sun who would never pull a move with such contempt like this.
Definitely Oracle being Oracle.
Now, there could be a vulnerability in one of the packages you built against, but exploitation of that is going to also depend on whether that specific program uses the vulnerable bits of code, using inputs controllable by an attacker.
It's mostly moot compared to the story here anyway, as none of the others are beholden to any entity resembling Oracle.