Also, new tech trends are not just hot air, there's also a lot of innovation happening. You just have to see through the hype and wait until the dust settles.
Reinventing wheels isn't innovation, particularly if the reinvention isn't round.
Sure, but I've worked with a number of individuals who have either resigned (on their own), or have been let go, solely because they had no desire or interest in keeping up with their craft.
I think that's effectively the same thing, though.
Ultimately, the notion of not wanting to stay abreast of the current industry trends is neither something I can relate to, nor is it something I see as being compatible with one's employability.
If you are successfully (i.e. the business or product keeps being developed) you still need to be aware of the internal weaknesses of your original choices and the external opportunities of updating to something more modern. The challenge is in managing the transition which is a skill in itself.
I assume that I hear about new stuff fairly early in their adoption, since I try to keep up with these things, so if it's still a thing two years later, it might have enough staying power to be worth learning. After that it still takes a while for me to get around actually learning the things.
Go and Rust are languages that have been on my todo list for a while now, for example, but I still haven't touched a JS framework because I haven't seen one with staying power yet.