There probably were a lot more of these travellers than we know of... anyone who didn't keep a journal, or show up in someone else's preserved writings, is lost to history.
I'm sure that these were often lost in the destruction of Baghdad, and other catastrophes to the world's written record. Also, the labouring seamen - who were mostly unlettered. But of accounts, there are still many such, from the Muslim world, between the rise of the Ummayids, and the destruction of that world by the Mongols and the plague.
There was a very high level of literacy in Islam, which had leveled most aristocratic social structures and replaced those with scholastic meritocracy - in general, if not universally. The tales of pilgrimages - especially by Sufi travelers to memorials of saints, etc. - are numerous, and show a diversity that spans individuals from Morocco or Spain, to those in India and areas that are now former Soviet republics, or Western states in today's China. These travelogues are often interspersed with spiritual discourse, lectures on etiquette and chivalry, or histories of Saints.
'Ibn Batutta is still a real prodigy in this company. His travels are unrivaled by those of B'ahauddin Nakhshband or Shah Nimatullah Vali, mostly a centruy later, or of 'Ibn 'Arabi, a century before. He also is one who produces a monograph focused on the travel as central to a history and documentary - instead of a peripheral circumstance, in a treatise on other topics.