Yes, if you simply need the same about of text in a much larger font then that implies you won't see the difference.
There is though a difference in the issue of weight reading for say 1/2 hour vs 4 hours. If you are reading normal paperback book sized text in single paper portrait mode that is reflowable then 10″ is much too big. If you are reading a multi-column magazine in PDF then 10″ is far too small.
This is why choice is good and it's handy if you can afford multiple sizes. Even having 6 different ereaders and tablets takes up very little space.
See
https://www.theguardian.com/books/pi...acking-cartoon
So a shame Kobo has no 7″ mono. They are easily a big enough company to have colour and mono 7″ models as they do for 6″. It's baffling that they killed the Libra 2.