We are in 2021 and we already know, or should know, what are the customer problems we have chosen to solve and what are the tools that will allow this.
If you chose to work with LESS, SASS, CSS, CSS in JS ... It is up to you to understand what each tool will allow you to build.
Whether it is a relational database or not, you only know why to choose it. ´
The important thing is that you know the reason for your choice in your project, and not to talk about how someone should work.