This is very true, even newer bikes that have more modern emissions are still generally exempt from the same standards as any car.
That being said if you have a high traffic commute it would still be faster for you to use a bike as well as better for everyone else in traffic so pros and cons.
Fortnine has a video that touches on the emissions/trying to be green and riding a motorcycle. The fact is most bikes not made within the last 10 years (and some that are) are carbureted and have little if any emissions control. Sure that Yamaha vstar250 might get 80mpg but that has more to do with having a smaller engine than a lawnmower than it does any modern engineering.