Call me crazy, but I suspect that Badspot and kompressor might want to update Blockland even more in the future. If they suddenly decided it would be a good idea to split their userbase right down the middle in this update, then future updates would either be slower than they are now by having to cater to the current version and a future version, or only be given to the new version.
You might say "sure, fine, as long as I never have to leave the Bedroom," but we all know it would only be a matter of time before someone starts bitching about one version being disproportionately better, and the choice you're suggesting becomes "do you want to turn off 40% of the game's cool features just for two old ones?".
What happens when someone discovers how to crash v20 servers, or some other horrible exploit? Do they have to violate their pledge to stop caring just to make the players who don't want to get with the times feel better? What if they had fixed it unintentionally in the updated version without ever knowing it, or fixed it in a complete restructure of the game's engine code? There would be nothing to motivate them to care for you.
Thus, the only option would be to drop support for v20. They could leave the broken v20 in with the game, but for nearly anyone, it would be a no-brainer option. v21 is just skipping right to that point, dropping all the issues and extra work that would stem from splitting their userbase, packing two separate engines and sets of base game scripts into one, ignoring the cries of those that they aren't supposed to care about, then ultimately patching the userbase back up again.
In the end, there's no avoiding it. Just count on the game being better this way. Even if it's not great at first, you'll get used to it, and then the fun begins.
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