Isn't ESPN+ strictly streaming? I don't think it is part of any cable service.
I have a subscription to ESPN+, but I access it through my Xfinity sports guide as it includes live ESPN+ games. I go to the sports guide, click on the graphic and I see the game. I also have access to all of the streaming services (Netflix/Prime/Max,...) through my Xfinity guide. They are all 2 clicks on my remote. It's very slow to switch back and forth between linear and streaming ESPN+ games, but its not impossible and I don't have to log in each time I switch.
I also have access to ESPN+ through my my computer.
With Spectrum, I do not have access to my streaming service through their guides. I have to use my smart TV and go through the internet.
From Xfinity's web site:
Streaming apps on X1 and Flex: Access to Disney+, Netflix, Prime Video, Hulu, YouTube, Max, and Paramount+ on Xfinity requires an eligible set-top box with Xfinity TV and Internet service. Disney+, Netflix streaming, Amazon Prime Video, Hulu, Max, and Paramount+ subscriptions required. Viewing uses your Internet service and will count against any Xfinity data plan. Streaming content limited to the U.S. Separate charges apply to On Demand and certain streaming services.