Yarn is generally regarded as not necessary anymore: https://medium.com/@vincentnewkirk/npm-vs-yarn-2019-e88757b1...

While hooks are generally regarded as faster, classes are actually much closer than previously though. But they still get beat out in the benchmarks: https://medium.com/@dan_abramov/this-benchmark-is-indeed-fla...

Firebase was bought by Google, which while there hasn't been anything in the news regarding Firebase, Google still collects and shares data. https://en.wikipedia.org/wiki/Privacy_concerns_regarding_Goo...