Not if you follow the normal safety precautions for using the AUR. There are several things you can do to look for red flags, but the most essential thing is to read the PKGBUILDs. And helpers like yay, paru and Shelly can all show diffs which makes that much easier after the initial installation because in most cases you’ll just see that the version and checksum has changed which means it’s as trustworthy as last time.

This has always been the case, and will continue to be the case unless the Arch team restricts the AUR which quickly can make it lose exactly what makes it so good.