As for the excuse that low appraisals are an obstacle, again, this is debatable.
From the theatlantic.com
After Williams put Arizona ahead, Brown's drive resulted in a debatable no-call.
From the stltoday.com
His in-game decisions during the final game in particular are debatable at best.
From the freep.com
The new lineup includes a prohibition against morally debatable experimentation.
From the nytimes.com
Both are iconic American images, though how actually real they are is debatable.
From the theatlantic.com
That is debatable, but it is a view that has been widely adopted by prosecutors.
From the dealbook.nytimes.com
And whether these countries benefit from charging visa fees at all is debatable.
From the economist.com
To what degree Cameron has a mandate to carry out much of his plan is debatable.
From the guardian.co.uk
This is of course utterly debatable, but it is still legally in vigor in France.
From the en.wikipedia.org
More examples
Open to doubt or debate; "If you ever get married, which seems to be extremely problematic"
Arguable: open to argument or debate; "that is a moot question"
Capable of being disproved
Debate or discussion in parliamentary procedure refers to discussion on the merits of a pending question; that is, whether it should or not be agreed to. ...
Controversial. Not fully proved, open to debate, sometimes used humorously; Of a person, argumentative; A fitting subject for debate
(debatably) In a way subject to challenge or worthy of debate
May be discussed. That which is open for discussion.