Less than 1% of global greenhouse gas emissions (And by my rough math, it could be lower than even 0.5%)

While many of the engineering improvements from racing aren't nearly as dramatic as they were previously (take the flappy paddle gearbox, for example). Nowadays, the improvements are lower level, think things like material science, manufacturing processes, and efficiency. But given the scale of the consumer vehicle market, these small changes add up very quickly.

Also, I dont think you understand what neglibility means. We would still be well on track for net zero carbon emissions even without sacrificing these culturally/socially significant activities.

The prime contributor to emissions by far and away is the industrial/power sector. Slight improvements there equate to decades if not hundreds of years of racing/football. A 5 percent decrease in either would easily account for thousands of years of both.

This is my problem with the "consumers need to do their part" rhetoric. We already are. The only reason things are as bad as they have been is entirely because of greedy mega corporations and governments who refuse to change due to corruption.