Actually no, because the use case is quite different. We wanted to create an umbrella that really has an app that helps. With Tile, you would just get the location feature, without the weather forecast
Also, your general use statement is all wrong. The biggest problem with umbrellas isn't losing them, it's them getting destroyed by a gust of wind or simple, unrepairable mechanical failures. A better use statement would be "Never get caught again without your umbrella/backpack/camera/etc."
Current technology has already solved the generic version of this problem. What you've done is solve this problem again, but only for a very specific use case, while requiring the user to buy in to a bunch of specific software and overhead that only helps them in that specific use case.