> "not supported" can mean anything from "physically impossible" to "we don't want you to"

More like:

from "physically impossible" to "we haven't tested that"

> they just couldn't be bothered to document all the possible combinations

Each combination adds exponential testing and documentation requirements.

Not tested != doesn't work. But that doesn't make not supporting it malicious. There are practical and financial cost to testing every combination, ultimately born by the consumer.