Ovinomancer
No flips for you!
Okay, here's a head scratcher for you, try to disentangle this: 5e has stealth rules, but has no rules to tell you how to sneak past someone.That's a far cry from "DnD doesn't have stealth rules," though.
To elaborate, 5e has a smattering of various things related to stealth, but the answer to "how do I sneak past someone" is not found in any of those rules or things, but in the simple, clear statement that it's up to your GM. There's no support for sneaking past someone, because the rules of the game provide nothing about how to do this except to dump it on the GM. The GM can decide to scoop up some of those scattered pieces, and do something with them, or just do something else -- modify them on the fly, change them entirely, do a completely different thing without any of them. All of these are valid responses, including using none of those rules at all. If the answer set to "how do I sneak past someone" includes using nothing else in the system, then it's very hard to suggest that the system has actual support or rules for how to sneak past someone. 5e avoids this by providing the pile of things the GM might choose to use, but then making it entirely on the GM if they need to be used at all.