Does "unsurprisingly disappointing" make sense?
If you're disappointed, it means that you expected it (or the thing it did/does) to be better than it really is. In other words, you're surprised that it's not as good as you thought it would be.
So what does "unsurprisingly disappointing" mean? You're not surprised by the fact that it's as bad as expected? Of course you're not surprised, because it's what you expected!
Should have been "unsurprisingly bad", right?
Source: last paragraph of https://www.techspot.com/news/80616-apple-new-mac-pro-isnt-good-cheese-grater.html and many other reviews on the web.
There is no contradiction here.
Critical is the definition of disappoint. From Google’s dictionary using New Oxford American Dictionary:
disappoint
fail to fulfill the hopes or expectations of (someone). "I have no wish to disappoint everyone by postponing the visit"
The article tells the story of making a cheese grater from material similar to the metal frame or covering on a Mac model. As a cheese grater, it doesn’t work very well. Surprise! Obviously situations can be imagined where one hopes for an unlikely outcome, and is therefore unsurprisingly disappointed.
Consider a teenager who doesn’t study and thus gets poor grades. His mother may be disappointed but not surprised.
From article:
the performance of the Mac Pro as a cheese grater is unsurprisingly disappointing.
Expectations aren't necessarily predictions.
MW has three relevant definitions:
1a : to consider probable or certain
expect to be forgiven
expect that things will improve
1b : to consider reasonable, due, or necessary
expected hard work from the students
1c : to consider bound in duty or obligated
they expect you to pay your bills
The new Mac Pro is likely disappointing expectations that fall under definition 1b or 1c. It is considered reasonable/dutiful that a cheese grater should be able to grate cheese. The unsurprising part is that computers are in fact not cheese graters (Even if they look like them) and as such are not predicted to be able to grate cheese well. They failing general expectations, rather than predictions tailored to their specific circumstances.
Another situation that comes to mindcould take place at a Grocery store. Manager A has a particularly difficult employee - Cashier B - who continually under-performs the company standards. Cashier B is disappointing with respect to the company standards, and consistently disappointing. Therefore Manager A would be accurate in saying that "Cashier B was unsurprisingly disappointing".
Overall, something can be "unsurprisingly disappointing", because the expectations that are disappointed aren't necessarily the logical predictions of the person that felt "unsurprised".