1. The devs have said that you will never lose your mech, and you will never lose your gear. (your gear/mech might need to be repaired, but it will never be fully taken away from you)
If this were going to be a super-niche subscription based game, then maybe it could get away with a super punishing setup like you describe. (a la EvE) However, this game is going for a broad appeal, and the majority of people don't like saving up to buy a shiny new mech, getting unlucky in their first match, and ending up with nothing to show for all their efforts.
2. C-Bills only become worthless if the Devs have stuff underpriced or are unable to release a consistent stream of content for purchase. For Example: LoL releases a new champion every two weeks, and the majority of the playerbase make no where near enough in-game currency to unlock each and every one as they come out. Sure, the top 1% that play the game constantly have hundreds of thousands of in game currency built up, but the economy of it works for the average player.
3. Allowing for bankruptcy is a deterent a lot of players. If you allow a player to completely lose everything they've worked for, a lot of players will feel downtrodden and discouraged. As covered in my first point, that sort of setup works for niche products that rely on subscriptions. It doesn't work so well for a F2P game that relies on a small percentage of its audience putting forward money.
4. They are going to allow you to buy in game items with real $. In the mechlab videos each mech and each weapon have both a C-Bills price and a MC price. (which is the real $ currency) Part of how PGI will make money on MWO will be to make cbill gain a slow steady process, so that you -could- unlock everything with enough time, but it will be much more convenient to supplement that with real $.
Honestly, I would be interested in seeing a super hardcore sim of MechWarrior/BattleTech like what you're suggesting, but I realize that this isn't the project that is going to do that for me. If you want to run a super-hardcore game like that your best bet would be to find/make a TT group with that specific type of game in mind.
Edited by LackofCertainty, 07 June 2012 - 04:15 PM.