I also see the same pattern in "Ask HN" posts and many comments here from people venting about how they've started so many side projects but can never finish them. Starting new projects is fun. Shipping things can be hard and requires some tolerance for boredom.
A lot of people get into the field because they like to program and play with new programming things. Regardless of jobs or compensation, there's a strong pull toward doing new and different things. There's also a strong aversion to working on someone else's project.
To throw another log in this rant bone fire, a few decades ago software was seen as harder and more expensive, and while there was some frivolous and/or stupid apps, big enough development projects were usually bound to some purpose.
Our industry in its current form is more open to build meaningless things and trash after a while. I knew devs who were specialized in home page redesigns, and they viewed it as facelifts to show the client company is still alive. It has a business purpose, but in the grand scheme of things the only person that really enjoyed the project was the guy using it to learn vue.js.
Or a team porting an app from Objective-C to React native, not because they think it’s shiny but because hiring is hard/expensive and/or the business wants to have one size fits all apps for iOs and android.
The FAANGs have tons of Objective-C code. The largest and most popular iOS apps in the world are actively developed in Obj-C and C++.
It’s absurd to me that mobile developers actively undermine their ability to get those extremely well-paid jobs by limiting themselves to one language.
The impact a language has on your career prospects is U-shaped. Knowing new languages is good for your career. Stagnating on an 'old' language is bad (Swift is only 7 years old...). But eventually knowing the old language puts you back in demand again, to port and support old codebases.
This just sounds insane to me being a non-programmer. Literally nothing in my job requires me to be up to date on technologies that are less than 10 years old to be considered for a job.
So my resume always needs to be fresh. I can’t be working with older technology because when it comes time to jump again, I won’t have the skills to do so.
Asking an iOS developer to work on Objective-C is asking them to sacrifice their future prospects.
Devs have a lot of the same incentives product managers do.