CodeIgniter, in it's wisdom, has been a very stable framework and not necessarily following trends in other frameworks. I think that as Laravel became so popular, many devs decided that PHP should not be done any other way. It's the hipster framework, and if you're not a hipster, then you can't be cool. These are the same types that must ride a motorcycle and grow a beard to feel like they're superior to us lowly coding peasants. So, if you must fit in and be cool, then that may change what framework you decide to use. If you want to get stuff done and CI is comfortable for you, then I think you should keep using CI. I've found no real downsides to using CI3, and may keep using it even after CI4 is launched.