Notes or Comment fields can be a tedious field to fill-in without the aid of a keyboard, especially if you have something wordy to input. Additionally, notes and comments fields are not well suited for common attribute table tasks say, querying. Honestly, as far as I can tell there really is no good reason to store these fields as text fields in the first place.
Wouldn't it make more sense to have the option to digitally write your notes and comments using a stylus, that is stored as an image, and gets attached to the feature service? For example, Survey123 already seems to have this capability as implemented within the signature field. The only problem with using the signature field as a way to take notes is the limited amount of space the signature field allots users. Maybe this is very simple fix; create a new field type called "Comments", and extend the amount of space to a full page, or as determined by the user.
So far I have been using the Notability app as a workaround, but being able to jot down comments, or take a picture and write directly on top of it with a stylus all within the Survey123 application would be a whole lot simpler, and a less clumsy approach. Filling out forms using a stylus; seems like a no-brainer!