I grow jalapenos each year so I can let some ripen. When they turn red the flavor is more fruity and sweeter and usually less hot though sometimes they might surprise you! I’ve had some red ones that seemed have no heat and others that hurt me some! Still good.
Sorry this pic is from the end of the season so these are a little rough but I want to show you two things about these peppers. One is that you can let them ripen. You usually will only find them in the store when they are green and will need to grow them if you want them red. Also do you see the one that is green with some black (probably dark green)? That is what they look like when they start to ripen from green to red.