"Suspicious" is walking up to the front door of your house and checking if it's locked. It's walking into your backyard without permission. It's looking in the windows of your house without permission. It's checking the doors on your car to see if they're unlocked. I'll even grant you that suspicious could be hanging out in a running car in front of an empty house for 30 minutes or so. However, it's not dressing flashy and being loud. (Though feel free to call the cops if they're being super-loud at 1am in a residential area. That's just rude.)
If your definition of "suspicious" includes "this person doesn't act like me" with a dollop of "this person acts like the cartoon black people I see in movies", then you should absolutely be prepared to be called out.
That pretty much just describes teenagers.
People can act suspiciously, sure. But that doesn't mean that behavior is actually correlated with committing a crime.
People are suspicious of a lot of things they shouldn't be. As other people mentioned in this thread, just being black and walking through a white neighborhood will get you plastered all over NextDoor.
Are you going to pretend like most people have an accurate, objective way to determine which behaviors are worthy of suspicion?
I don't know. Are you going to pretend like there are no way for people to act suspicious now?