That's up to you, and society. Do you accept that tall people exist?
Right. Now exactly what height do you need to be a "tall person"?
This is the same. I haven't used it so I can't say how optimistic their "drop-in replacement" claim is, but they certainly don't need it to work 100% of the time with 100% of project with 0 changes to make that claim.
"Drop in replacement" makes an implicit guarantee about utility. It sets expectations about what I'm able to accomplish by investing time and effort into a solution. I don't expect tall people to have any specific utility.
If you call something a drop in replacement and it is not a drop in replacement, it's simply a lie.
That's up to you, and society. Do you accept that tall people exist?
Right. Now exactly what height do you need to be a "tall person"?
This is the same. I haven't used it so I can't say how optimistic their "drop-in replacement" claim is, but they certainly don't need it to work 100% of the time with 100% of project with 0 changes to make that claim.