The Simucoin example was just a generalization of
you can double down the points in one instance, you dern tootin’ skippy (means ‘damn well’) should be allowed to do it the other way
to other conversions, using a somewhat extreme example including dollars to try to illustrate that Premium and Platinum points are completely separate currencies even though they both are called "points".
I could increase Platinum subscriptions by 10% alone (totally made up and fabricated, but I’ll be the team could come up with that actual number) just by allowing it
I actually don't think that's how this playerbase works. Now that they have offered Premium to Plat conversion, people are going to ask them about converting the other way. If I was Simu, I would say something like "Not now, but maybe we'll consider it in future" which is honest even if it is very unlikely they plan to ever offer it. Unless they outright confirm it will never happen, a non-trivial amount of people will speculatively upgrade to Platinum just in case it happens because double Premium Points for an extra $10 per month seems attractive. I suspect that some non-Plat players already have Plat subscriptions for this reason.