All modern moral systems have extremely serious defects where they can be gamed. Repugnant conclusion, the entire concept of deontology, etc. Virtue Ethics is ungameable.
Virtue ethics is gameable if you can make virtues conflict.
Which is trivial: pro-life vs. pro-choice, free-speech vs. anti-harassment, etc. I don't think there's anyone on any part of the political spectrum who thinks their ideas are not virtuous.
This is a feature, not a bug. Casuistry is the science of determining the correct course of action in a complex situation. It’s complicated because the world is complicated. Attempting to create a moral system from first order logic (deontology) or a linear system (utilitarianism) was doomed from the start.