I appreciate that you’re considering the ramifications, and yes that would solve some of the issues.
However, let’s thought experiment out how this could work in a real world scenario. I apologize in advance my examples will be from the earlier days of the game because I haven’t played recently, but the concepts should still make sense.
Let’s say you’re a rich guy now with a handful of 2ks and you decide you want to level up a 6 wizard grinder team.
Organic gameplay with no MTX influence might look like the following:
Buy a half a dozen enchsnted Mageblades from players who have them for sale
Enchant some random BoCs and BoNs you have lying around, and buy the rest you need to kit everyone out
Get to grinding
When things start to slow down, buy as many Seer’s Sabers and sets of expert gear you can find for sale, enchant them, and replace any that blew up as many times as it takes for you to be satisfied that it’s time to move on
Sometime on the way to 1k, start kitting your characters out with the “chase” items like EB, HC jewelry, etc.
At 1k, work on collecting the rest as it comes up for sale
Continue for whatever gear there is between 1-2k
What have you sunk out of the economy?
A dozen or so Mageblades and sets of Expert gear once it’s all said and done, due to enchanting explosions and stuff
Enough “high level” items and “chase” spells to optimize your grind to 2k
As much 2k gear as you can get your hands on
Now, the same goal but you can buy levels:
Roll 6 wizards with the stats you want
Buy XP
Start buying the best gear for level 2k
Never waste your money on mageblades, expert gear, seer’s sabers, and other low level gear because it’s not going to speed up your getting to 2k. You’re already 2k.
Work on collecting the rest of the 2k gear as it comes up for sale
What have you sunk out of the economy?
The same amount of 2k gear
The same amount of “chase” spells, unless maybe you skip some because they were good for leveling but not really useful at 2k
So what does all that mean?
Little Timmy who’s just trying to play the game without paying to win finally gets a Seer’s Saber to drop while he’s leveling up his characters. “Hell yeah,” he says! These things have been going for millions! He goes onto the auction channel to sell it. But there are 50 of them for sale because only the other Little Timmies who are leveling up for themselves would need them, and they can’t afford to keep one rare item when they could instead turn it into a full set of enchanted “good” gear. So someone trolls you with an offer for 10k because the Seer’s Saber is the new Vulcan Edge. You can’t give that shit away.
So now as a new player, you have no meaningful way to enter the game’s economy, because ALL the value is concentrated in the items that people at 2k need. It doesn’t matter that not everyone is buying their levels and that some people are running their first characters up to 2k, because that’s much fewer people than if everyone needed leveling gear. The demand can’t keep up with the supply that is already in the game from the pre-buying-level days.
Now, there are things that seem like they will mitigate this. The crafting system is going to create a sink for those low level items and high level players will still pay for them just to melt them down, right?
Well those high level crafted items absolutely must command a value greater than the price of their components, or no one will use the system. So high level weapons are still selling for X * y * z, where x is how many low level items you need for a craft, y is the cost of one of those items, and z is a multiplier for the amount of profit the economy settles on people willing to pay for the craft. If X is too low, you don’t sink enough Seer’s Sabers out of the economy to make a dent in the supply:demand issue I mentioned above. If it’s too high, you’re back to the amount of money a low level player can make being meaningless, because you need to loot dozens of Seer’s Sabers or whatever other relevant low level item to ever be able to afford high level gear.
The whole thing is really, really complicated and I won’t pretend I’ve explained every single detail in this wall of text. You can rip it apart if you want and I’m sure we’d have to debate for days and days about why there’s no silver bullet to make MTX XP not affect the gameplay experience of subscription-only players. I just hope I’ve raised enough points here to illustrate that everything is connected in these online games. How you play as one single player won’t be enough to really alter the course of events, but once more than a handful of people take advantage of cash-for-XP, it puts a strain on the delicate balance of the economy.