The new receivers do have apps like Spotify ( and others ) built in -
https://usa.denon.com/us/product/hometheater/receivers/avrx3600h (https://usa.denon.com/us/product/hometheater/receivers/avrx3600h)
BUILT-IN BLUETOOTH AND WI-FI CONNECTIVITY
The heart of your wireless network. For Bluetooth, Wi-Fi and AirPlay 2 wireless streaming connectivity, the Denon AVR-X3600H is equipped with an advanced dual antenna transceiver system for robust streaming even in congested urban environments. Enjoy listening to your favorite audio content wirelessly from your smart devices.
With HEOS Built-in technology play the same song in every room or select a different song for each connected room — the choice is yours. HEOS works with Amazon Alexa and Google Assistant, providing effortless voice control.
HEOS supports free and premium Spotify, Pandora, Amazon Music, TuneIn, iHeart Radio, Sound Cloud, SiriusXM, Tidal and more.
There is something to be said for getting a new receiver - 10 years is a good run for your current unit, but it's certainly missing the features of the new ones. Maybe JD can chime in.