It isn't random.
Firstly I think it is mostly directed at the abuse of JS that we see.
Secondly while there has always been good reasons to avoid running code in the browser unless there is a good reason.
This year added one more with the CPU level bugs that could be exploited through client side JS.
From what I hear from the junior devs, what they're teaching in school these days is that as much of the site as possible should be offloaded to the client device in order to free up server resources.
The mindset is that everyone in the world has unlimited massive bandwidth at all times, along with the latest gear; and if you don't, you're an "edge case" and should be ridiculed.
Offloading to the client device in order to free up server resources quite often means taking the load your server could handle once and multiplying it millionfold, once per each of your million visitors. In other words, your product just started to burn a million time more electricity than necessary. We should call it by its true name - externalizing costs - with all the negative baggage associated with that phrase.
Network is much slower than CPU. It's ironic you deride the assumption that everyone has unlimited bandwidth and then suggest that the solution is to send every user interaction through the network.