Tags are great but I still want my folders. Also doesn't help that the way google describes some things is unnecessarily complex or confusing. For example, removing an email from the inbox requires archiving it. In most other applications (WhatsApp, Signal, Outlook, etc) archiving usually results in the email being placed in a specific archive folder that isn't readily accessible through the UI. At least not to the same level that normal emails are.

People in my work and personal life experience do not understand the concept of labels in a Google inbox and misname them folders 100% of the time. Google allows you to drag-n-drop emails "into" labels like you would files in folders conflating the issue even more as the logic to automate this behaviour with a filter isn't leveraged. Even the layout of a default inbox is setup in a way that the average user has difficulty understanding what happens when an email drops off the "front page" of their inbox.

They can be nested, the one thing I have never been able to figure out though is how to get alerts of receiving a message while also filing away in a sub folder. You get one or the other in outlook, as a result I rarely check my work email anymore cause I either get the fire hose of spam or miss everything entirety because it's going to a folder and not passing along an alert about a new message.