1. Set up a Siri Shortcut "when alarm goes off, play Spotify". Haven't done it, but having been knee-deep in Shortcuts this weekend, I'm confident that it is possible, and (on latest iOS) not difficult even for a Shortcuts n00b. (For Android, I know Tasker can do this.)
2. Fiddle with buggy and not-maintained-as-soon-as-it-shipped application to set alarm clock. Application must run on a computer that, coincidentally, can serve as a full-function WiFi-enabled alarm clock and can set its own damned time.
The OP wasn’t defending this specific model. Just having an alarm device in genera. So #2 isn’t the only alternative. Even something like an Alexa device is an alternative. where app is optional.
1. Set up a Siri Shortcut "when alarm goes off, play Spotify". Haven't done it, but having been knee-deep in Shortcuts this weekend, I'm confident that it is possible, and (on latest iOS) not difficult even for a Shortcuts n00b. (For Android, I know Tasker can do this.)
2. Fiddle with buggy and not-maintained-as-soon-as-it-shipped application to set alarm clock. Application must run on a computer that, coincidentally, can serve as a full-function WiFi-enabled alarm clock and can set its own damned time.