Yes, it is quite good for rescuing data etc. because in a lot of cases it is the screen that fails.
In your case where the backlight dies it often helps to shine a flashlight on the screen and it will usually become more intelligible.
One thing to keep in mind is that android will revoke saved debug-computers after 7 days or something meaning you have to press a popup to accept the connection. You can turn that off in the developer options and then you won't need any interactions on the device to start scrcpy (as longs as it is a computer you've used before with adb).
In your case where the backlight dies it often helps to shine a flashlight on the screen and it will usually become more intelligible.
One thing to keep in mind is that android will revoke saved debug-computers after 7 days or something meaning you have to press a popup to accept the connection. You can turn that off in the developer options and then you won't need any interactions on the device to start scrcpy (as longs as it is a computer you've used before with adb).