According to the latest Steam hardware survey, nearly a third of active Steam users are playing on ten-year-old GPUs, and even most upgraded systems fall into low to mid-range performance tiers. About 75% of users have GPUs with raw power slightly above, or even lower than, a GE Force 1080 TI released in 2017.
This shows the importance of optimization for a variety of hardware, and raises the question why so many companies are neglecting this aspect of development in modern titles.