Please help me understand whether Graylog is better/easier/simpler than ELK?
A quick glance through the docs and it looks very similar.
It's a lot easier to set up and manage in my experience. The interface is very user friendly. It all depends on your specific needs of course. ELK is a bit more performant I think, although I have never compared them properly. Both have good scaling capabilities.
One thing it has over ELK worth mentioning is that it has authentication in the open source version. Also able to configure it more through the web interface than ELK.