Is why do we want to have people use their nodes sooner.
It provides a better user experience. We know that people will install the software and immediately start trying to use it. We know that user education is never a good solution. We need to design the software such that uneducated users still have a good experience, and part of that is making the software usable without having to wait a long time. We want to make software that doesn't result in unnecessary complaints and support requests.
Even now you can install and try to donload the blockchain on too small a drive, it has the pruned check box on by default
It only checks it by default when the free space check determines that the drive doesn't have enough free space for the full blockchain.
but does not even mention what may happen if you un-check it.
When you uncheck it, it shows a warning that says the entire blockchain will be redownloaded. This isn't "no mention of what may happen".
YES you can still do that now by installing on a 512 GB drive and running out of space, this just seems to encourage it. Once again IMO.
How does assumeutxo encourage running on low spec hardware? The same system requirements checks are being run regardless.
Regardless, making software that can run on low spec hardware is never a bad thing. Something that can run okay with little resources is something that can run fast on decent hardware. Optimizing is never bad.