[ps67]

Dimensions of reader can vary from 5" (Kobo Mini) to 13.3" (Onyx Boox Max Carta and Max 2). Nothing with fixed layout can give good experience of reading with all readers.
The most used dimension is 6", although are increasing user of 7" or 8" screen dimension devices. Fixed layout should not be used if it is not absolutely necessary. And "My client likes fixed layout" is not included in the absolutely category because most person will hate the book.
I (but all of us) want to change the font, the dimension of the font and its sharpness. And I personally change also the indentation and other things if I am not satisfied. I bought a book with fixed layout and I can't read it.