I would say that you could. I don't say anything saying you must apply for permanent resident status after 5 years - only that you may. Out of curiosity, why would you not want to? (ignore that or tell me it's none of my business if you don't want to say, of course)
By the way, the periods of validity changed early this year, and the initial permit is now issued for a period of 2 years, subsequently renewable at 3 year intervals. Here it is from the horse's mouth, which also supports the notion that the renewal can be effected more than once :
Without prejudice to any special legal provisions (as when the Aliens Act provides specific different deadlines), with the amendment introduced to article 75 of the Aliens Act, by article 192 of Act n.º 75-B/2020 of 31 december – State Budget to 2021 in force since 01/01/2021 and to 2021 –, the temporary residence permit is valid for two years [and not just one] from the date of issue of the corresponding title and renewable for successive periods of three years [and not just for two].
Note : "renewable for successive periods" not "renewable for a successive period"
Also, there's now an online process for renewals of residence permits