"...please don’t make the behavior of a command-line program depend on the type of output device it gets as standard output or standard input."
https://www.gnu.org/prep/standards/standards.html#User-Inter...
Of course you don't have to follow their standards, but their rationale for this particular item is reasonable.
I think a warning as described in the article is perhaps just about OK though.
And I go around piping things into 'less -RS'
I wouldn't get the warning.
Though of course getting it to some is probably better than none so I'm more than likely with you.
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Unfortunately many apps do behave differently towards ttys in one key way - colour.
It is somewhat frustrating to be piping into less something like 'apt list --upgradable' and being unable go essuly scan because its a mess without colour.
To use an analogy from web browsers, the equivaleny guideline would be asking websites not to detect features by reading the User-Agent, and using feature detection instead.