Let's take the M48A5PI as the example here.
First, remember that -56% is On Average. Having good games still equals more silver overall.
But, back to our tank. Currently it earns us about 29,000 Net Silver on average
On Jan 30th, that's going to decrease to about 17,000 Net Silver.
(That's actually only about a 42% decrease)
Now, that's our base earnings. On top of that, there's the premium accounts, Challenge rewards and more. Let's say you only have the Silver Bonus from the season, that's on average 21,250 come jan 30th. (For the current average games, that's about 36,250 silver)
In comparison to the let's say the PI's gun module (a much cheaper 350,000) that's 16 games to get silver to fund the gun compared to a massive 55 games under the current system.
Now here's a second but! These are all averages, based off as much data as we have. If you have a good game, you can still have good silver earning games meaning that -56% is simply that, an average. Your games will still determine how much silver you bring back to the garage