There is pretty much a global SE policy for this, which goes like this:
Does the edit improve the post in some way? Making it easier to find or easier to read/understand? If none of this is true, it should be rejected as "no improvement whatsoever".
This applies here - the edit should have been rejected. The edit does not make the post easier to find, read or understand. Normally, correcting grammar/spelling errors do make posts easier to read/understand, but in this case the change was so minor that it really doesn't add anything.
More importantly, edits should address as many issues with the post as possible. Looking at the question, it is actually a rather bad one (despite the number of up-votes). Comparing a FPGA with a CPU is a very broad topic, and not necessarily meaningful unless specific hardware is mentioned. How to measure performance of a CPU is a very broad topic in itself. A complete answer to it would require the poster to write a whole book.
Digging further into this, we realize that the question was posted as "answer your own question to share knowledge Q&A style". This is fine, but questions posted this way need to live up to our general standard for questions. Just because you have a great answer coming, it doesn't mean that it is ok to write a sloppy question.
This question should have been closed as "too broad", not fixed!
Now, as it turns out, people have taken lots of effort posting answers to that question, so it wouldn't be a good idea to close it at this point. And EE tends to be more lenient towards overly broad questions than other sites on the SE network.
The proper course of action would probably be for a diamond moderator to put a "historial lock" on the post, meaning it will be preserved, but it is not a good example for how questions on EE should look like. This will also block further edits.