That you need to either like, or write the genre you are critiquing for another writer, I feel is a bit of a misnomer.
Whereas this can perhaps give you an insight into what the writer's intentions are or the nature of their world building, it can be a hindrance.
Let me try to explain what I mean.
To begin with all authors world build. By that I mean they create the world in which their characters inhabit. It might be just a suburban street in January 2017, London in 1900, Mars in 2359, or a world where dragons rule, but they create the setting for their story. This setting has to be logical within the perimeters that the author creates for the story. If using a real historical time period it has to sound, look and feel right to the reader. If extrapolating from a time period, say, roman, for a fantasy novel it has to fit, same for a SF novel using abstract theory and technology. The author has to ring fence his creation and make is plausible and more importantly convey this to a reader. This is where a lot of writers starting out tend to fall down. If you can't get over the nuances of your world to the average reader, then you have hamstrung your work at the get go. You need to show the reader your world, without drowning your prose with information. Word choice, images, emotional response to the world by your characters, tone and texture all play a part. This is one of the elements you should show and expect from a critique. Is my world clear, does it make sense within the framework? If someone has given a critique and has mentioned elements that confuse them, or don't quite feel right, please don't dismiss the critique as the reader not understanding your work. Look again at the work, try and see what they are seeing. You might find things are not as clear as you believe them to be.
I often critique work that is in other genres. (especially at my face to face group) Just because I don't read those genres for my own pleasure does not mean I can see plot holes, character errors, flow, tone and errors in sentence construction, info dumping etc, etc. I have found that looking at others work, no matter the genre, does improve my own. Limiting myself to the genre I write in is a hindrance and can be self-limiting. I don't just want to appeal to genre readers with my work, I want others, who do not normally read the genre, to take a chance, so my writing has to be a strong as it can be. Having people that write in other genres critique the work does help.
I have over the past two years worked with editors from very different backgrounds with regards to my published novels, each has seen things I haven't, each has offered insights to to plot, characters, and world building. I certainly haven't dismissed their suggestions, same as I haven't done with anyone that has critiqued my work. I look at all the comments and try and understand why the remarks have been made.
To be blinkered by your genre is not doing your work justice, you need to be open to all genres to create the story you want too, as no genre is completely separate from another, all have small elements of the others, all rely on creating believable characters in a believable situation within the framework the author has created for the story.
As regards critiquing work; you need to have an open mind from the first word. Do not begin to re-write, or alter the world the author has created to suit what you believe it should be. Look at plot, characters, information on the world, flow, tone, pace continuity, sentence construction and grammar. The story might not be to your taste, but you can see what works to move the story forward and what doesn't.
This is why a good critique group/beta readers who have an interest in a number of genres is a must.
(Disclaimer: not getting at anyone, just putting my thoughts on the subject down, and is the longest post I have made for a number of years
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