I will give them the benefit of the doubt that they properly auditioned it in their own system.

Gosh, your benevolence is overwhelming. What a thankless burden your superior audio wisdom must be.

"More than 80% of Apple Music subscribers listen to spatial audio"

While I applaud the OP’s enthusiasm and positive demeanor, I’m still scratching my head. A few points I would like to make ...

Being an audiophile has never been about winning the popularity contest. Whether it’s our choice of music, equipment, or room setup, audiophiles always have and always will be a niche group that does not represent the broader music industry in any shape or form. Throwing around metrics about apple, etc. is kinda useless and not relevant to this crowd.

Unlike what the OP thinks, many of us started with multi-channel systems and have come to prefer two-channel audio, despite its supposed weaknesses. Not everyone is looking for an immersive experience where you’re in the middle of all the action. So the assumption that most audiophiles don’t know what they’re missing vis-a-vis multi-channel (with or without atmos) is rather naive. We tried it, many of us still have it in our home theater systems ... and we still prefer two-channel. My nephew is big into spatial audio (headphones) and I’ve tried listening to it several times. Yes, it is different and enjoyable but not something I would like to listen to for hours at a stretch. Perhaps that might change as more artists convert their recordings to spatial.

As far as allocating budget goes, it is a very personal decision. Some of us want to invest in one system and take it as far as we can. For example, if I have $1000, I will build the best 2-channel system for $1000. If I have $50,000, I will build the best $50,000 2-channel system I can for $50,000. It’s all about your priorities. Telling people how they should allocate their budgets will always make you look like a pushy know-it-all, hence the pushback from some members.

Interesting interview of Bon Ludwig in Stereophile.

 https://www.stereophile.com/content/bob-ludwig151the-mastering-master-bids-farewell-part-2 

Not an Atmos fan:

”What is it about Atmos—Apple's version at least—that Bob doesn't like? First there's the fact that it is a lossy-compressed format, akin to (though more sophisticated than) MP3 or ACC. "With Atmos, we're going back to a lossy world. ... It screws up the sound in so many strange ways."

Also, "There is no way to remotely guarantee how the listener is going to listen to it." That's a big part of the point of Apple's Atmos. It could be via a pair of Apple's Atmos-supporting earbuds, or a smart-speaker gadget that throws sound around a room, or a real-deal immersive listening space with speakers around the room and on the ceiling. "When it's done really right in a great system, it's impressive. It’s still not lossless high-res, but it can be impressive. But, that is few and far between."

In the case of a hybrid SACD, there is usually a 2-channel stereo layer with its own discrete stereo mix. No such layer exists in the "immersive" formats, including Atmos. Instead, a "binaural" version is "folded down," derived from the multi-channel mix.”

For me, it doesn’t really matter.  I listen to vinyl about 95% when critical listening.  I find that the optimal amount of single malt scotch - not too much, not too little - maximizes the immersive experience!