I think every technology that's widely used today that requires some backward compatibility is here to stay for a long time.
Things like API/protocols are hard to move from.
As for new technologies I would expect them to appear and take the niches where current technologies are not good enough. Take C++ vs Rust for example: the former is quite bad in terms of security and the latter is good at that. So Rust will become more popular in writing security critical applications and web services. But C++ seems to be good enough for things like high performance/scientific computing so it will be still widely used there.
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I think every technology that's widely used today that requires some backward compatibility is here to stay for a long time. Things like API/protocols are hard to move from.
As for new technologies I would expect them to appear and take the niches where current technologies are not good enough. Take C++ vs Rust for example: the former is quite bad in terms of security and the latter is good at that. So Rust will become more popular in writing security critical applications and web services. But C++ seems to be good enough for things like high performance/scientific computing so it will be still widely used there.