Alexander Lau is spot on!!
If you don’t “use” a framework, you are absolutely building your own. You just have no benefit of insight or feedback from the community, or a company (i.e. Facebook) that has poured significant resources into making the framework robust, capable, and all sorts of other things a good framework entails.
I suspect his issue is with Ember. I took a brief look at that some time ago and said no way. There are frameworks, then then there are FRAMEWORKS. Some are pretty restrictive (my take on Ember), and some are “use as much as you want”, i.e. React. I can use React on part/most/all of an application, and the other parts can do what they want. This same thing applies to other ‘frameworks’, such as Vue, and Angular. Use them where it makes sense, go native where it make sense.