For consumer software, yes, most is still being built with a baseline target instruction set from the early/mid-2000s. In 2019 there were reports of Apex Legends requiring SSE4.1, an instruction set from circa 2007. It will be be probably close to a couple decades before consumer software would start commonly requiring these instructions.

However, for more specialized environments, such as scientific and high-performance computing applications, its much more common that you will be using custom software designed for a specific task, and that it's normal to recompile the software when you get a new set of hardware. In those applications, these instructions can make a huge impact, as you know exactly which capabilities are supported by the hardware and can use everything available.

I believe there are also some (possibly limited) situations where a program can check what instructions a processor supports and use either the newer (higher-performance) version or the slower, more widely-supported version depending on that check. There may be limits on how often that can be done however.