Unfortunately, this will always be a possibility as Photoshop evolves and makes changes.
The way Photoshop Actions work is quite similar to code. If one thing stops working, the whole program will likely break. There have been some very small changes Photoshop have made over the years which have affected Actions, but nothing too dramatic that I have not been able to fix.
With every Photoshop update, I quickly run through several of my Actions to test whether there has been any Photoshop functionality changes that affect Actions. If there has been, I identify the issue and then proceed to test all 100+ of my Actions to see if they have been affected, I will then work to update each Action that has stopped working.
This process of checking the Actions and updating them can take a few days to a few weeks, depending on how many Action are affected. If all 100+ of the Actions are affected, then it could take a few weeks for me to fix them and then re-upload them all.
What if you want to use the Action right now while waiting for me to update them?
Well, there is a quick and easy solution! For Creative Cloud subscribers, you have the ability to load earlier versions of Photoshop. This means that no matter what happens in the future, once an Action has been tested and working on a specific version of Photoshop, it will always work on that version!
In the unlikely event of a major Photoshop update that completely destroys an Action and is unfixable by the author, this option of additional versions of Photoshop will always be available to you!