My idea of a major overhaul for a client is upgrading from Mysql 5.7 to 8 with no downtime and then slowly, over a year, finding queries that could be sped up with lateral subqueries or window functions. That's about the pace, and it's effective at keeping resource use in check. The wilder things I experiment with on the side are once in awhile actually useful for a new app or service...
I basically agree with you, if the cost of building the code will be easily outweighed by the savings to the client and I also think the platform will hold them for the next 10 years, I'll pitch it [e.g. I've moved many early clients from my servers over to AWS services when it made sense, and still maintain them]. But it's easy to see too how if I were trying to constantly drum up more work, it would be seductive to pitch them on new hyped up technologies they don't need, just to remain relevant and keep the checks flowing. I think that's the animating force behind all of this platform churn, not excited developers who just want to sheep or yak-shave (thanks. I always forget which ruminant I'm shaving ;)
I basically agree with you, if the cost of building the code will be easily outweighed by the savings to the client and I also think the platform will hold them for the next 10 years, I'll pitch it [e.g. I've moved many early clients from my servers over to AWS services when it made sense, and still maintain them]. But it's easy to see too how if I were trying to constantly drum up more work, it would be seductive to pitch them on new hyped up technologies they don't need, just to remain relevant and keep the checks flowing. I think that's the animating force behind all of this platform churn, not excited developers who just want to sheep or yak-shave (thanks. I always forget which ruminant I'm shaving ;)