The Standard Model is not wrong, in the sense that it works extremely well to describe all the phenomena observed so far. However, there are issues that make us believe that it consists only of the tip of a huge iceberg that we need to discover. The violation of lepton universality may be a way to get under the tip :)
In short, even if the ultimate theory is not the Standard Model, in the low energy limit that has been probed so far, the ultimate theory will be identical to the Standard Model.
I recommend maybe this post of mine if you are interested by the reasons to go beyond the Standard Model :)