We at Lightroom Guy are always keeping our eyes on MacOS issues and we're still holding off on updating to Catalina. It’s not ready for prime time. At least not for us, so we can't recommend updating to Catalina to our clients and readers.
We've been getting quite a few questions about this issue. So we thought it would be a good idea to address it in a blog post. Should you update to Lightroom version 9 and upgrade your catalog? The short answer is: yes!