New SMS messages have stopped showing in Messages on Mac or iPad

I've been a Mac user since the 80's, and an iPhone user since 2008. I've had an iPad since the first iPad release, and currently use an iPad Pro 12.9. Oh, I also wear an Apple Watch 4. I use a paid iCloud 2TB account to sync everything between devices. And I am also a software engineer with 37 years experience, and am used to figuring out my own problems, but am stumped on this one.

I've noticed in the past several weeks that I no longer receive SMS messages from non-iPhone users, such as my BOSS (president of the company) anywhere except on my iPhone 11. I typically don't bother to keep my phone within reach, because with wifi everywhere, messages should show up on my watch, my iMac, my MacBook Pro, or on my iPad Pro.

I've checked all the usual settings. Text Message Forwarding is enabled on the iPhone, with the iMac, MacBook Pro and iPad Pro all selected. I've signed in and out of iCloud on one of the Macs. All devices are up to date on the latest software, and all devices have all of my iCloud accounts and my phone number selected for where I can be reached at, with my phone number as the source to start new conversations from. iCloud messages is enabled on all devices.

The iPhone, Apple Watch 4 and iPad are all running the latest of their respective OS. The iMac 27 is running macOS 12.5, and the MacBook Pro is the latest Big Sur version, whatever that is. All devices are on the same wifi network.

From best I can tell, looking at the message history on my phone versus my iMac 27 and iPad Pro, I stopped receiving SMS messages from non-iPhone users on the computers and iPad some time since mid May, but that is about as close as I can estimate it.

Somehow I feel this is an iCloud issue, but it is not specific to the Mac since my iPad and even my Apple Watch are also impacted, so I am putting it under iCloud for now.

Any advice that has not already been tried is appreciated!