World standards, record presets, or minimum standards all seem to be the same thing. You're 100% correct that they are simply a placeholder for a proper record. The IWF has an excellent explanation here on how they're calculated. One thing that's neat is at the bottom you'll notice:
The Working Group agreed that the World Standards/Records should be reconsidered after 2020 and in the categories where World Standards still exist the highest athlete performance shall be considered as World Record.
The IWF plan on doing exactly what you mean. Taking the highest athlete record and simply making it the IWF world record. Now of course this is specific to the IWF but the methodology is the same across most of the powerlifting federations. The IPF seems to still have minimum standards in uncontested categories but the CPU, for example, shows "0.0 kg no minimum" as their placeholders. So in this case it's exactly what you said, someone just has to compete.
A pro is definitely avoiding having embarrassingly low records. Powerlifting federations compete for competitors and as much as it may seem like having low records is encouragement to go break them, too low would make the federation seem like a joke. Imagine seeing that the 230 lb men's open bench record was 135 lb.
In 2011 the IPF decided to re-work all the weight classes so at the very end of 2010 they retired all records that were held at the old weight classes. So, another pro is the amount of paperwork you'd avoid. Every time an athlete breaks a record it's not just a webpage update. The record secretary for the federation will take their record submission, put it in the database, and make them a certificate. These are the federation records we're talking about too so this isn't just a local or state record, they could literally mean world record.* This could be 100s of submissions per day.
Additionally, the standards aren't really that outrageous. I think having it there as a goal post could very well encourage some people to try. For example, I thought the least populated would be the IPFs Masters 4 Women's record. If you look we can see that for squats, the -63 kg is 95 kg (record), -69 kg is 85 kg (standard), and -76 kg is 105 kg (record). The standard is lower than what you'd typically expect (lifts going up as weight class increases).
* "World records" are per federation as there is no real unified set of records. Every federation has their own rules, thus every set of records is done by those rules.