Looks like your passport was under the corner of a metal paper holding system of sorts with liquid and/or heat source nearby that has caused that kind of damage before when the passport was pulled out or being used to press in an issued visa. But at this point the cause of the damage from sloppy handling won’t really change a thing.

Singapore may not make a significant issue over that kind of damage which Indonesia may make into a travel show-stopper. While it may not be a big problem if denied entry to Batam with its short ferry from Singapore, I wouldn’t want to fly from SIN-DPS on such a passport with that kind of damage. SIN can be fussy at times too, but if you have SIN-issued travel docs of sort that are presented in conjunction with the passport, SIN is most probably going to let you in eventually and may suggest you visit the Embassy in Singapore to begin the process of getting a new Dutch passport.

The more likely problem will be the airline, if they exam the cover. I wouldn’t expect to use that passport for very long before encountering an airline rep who uses it as a reason to deny check-in and/or boarding. It’s not the fading of the gold print that would concern me. It would be the burgundy cover color removal in the corner that looks more obviously as damage than routine normal wear.