Spending a little extra money on a more expensive brand of something you really like can be worth it.
It's often not worth it to do the "right thing" and save money by buyinh a generic or off-brand item you'll end up not being happy with. Assuming you can afford the cost, the disappointment of eating off-brand cereal that tastes like paper, factory-farmed eggs, or wearing discount clothes that are cheap and look bad or have an odd fit just isn’t worth it.
What else there is will vary greatly depending on the geologic context of the hot spring. Along with water vapor there can be gasses such as carbon dioxide, hydrogen, hydrogen sulfide, helium, radium, argon, methane, and I'm sure many other things.
I remember similar articles when Windows 7 reached end of life. People will complain but mostly adapt to Windows 11, and Linux will gain 0.2% market share.
I thought Agatha Christie made Belgium up?!