If it was that easy, we'd all have GAs for less than 2K.
However, maybe look at it from a different perspective. Do you really need a full GA that covers pretty much all transport across the country? Maybe a regional GA would suit your needs better? A half-tax card is also something to consider, depending on how often you use transport.
You can also pay for the "full" GA in monthly installments, so it's not quite such a whack to the budget in one go. Look for the subscription option on the SBB website.
I'm not an expert since I just use a half-tax and I'm in Bern. I believe you can get a GA for just the Zürich transport system, for example. Even for certain zones. Here is the website for more info:
For instance, the Basel area has a regional card that covers the northwest corner of the country. All travel within this area is free. I then have a Halb tax card for when I travel out of the region.