I would hand Barack Obama himself my phone and he can have at it.
Something, though:
Anything sensitive on my phone - financial stuff, whatever - is password protected and has other encryption. So how would that work? The actual phone data is one thing, but what about other accounts and apps?
That gets to the heart of the issue. No, what the FBI is asking for would not automatically open up everything that's on your phone (and elsewhere for that matter) for everyone that wants access to it. But it would make it much, much easier for those that are motivate, and who have some tech savvy, to get access to it.
Think of it this way. Apple (and others) have managed to create - with considerable cleverness - one really, really, really good layer of protection for that kind of stuff, really for anything you choose to protect (some people choose convenience over such protection in how they set their phones up, which is obviously fine - their choice). If that layer of protection is defeated, the hardest part of the job - for all kinds of potential bad actors - is done. They can get around other aspects of security, it's just a question of how badly they want to. But that first layer is a bitch, it's really well designed. That outer wall is really, really tall. Let people through it and you open up all kinds of possibilities for bad actors. That's why it's so important to keep people outside that first wall, it's the only line that can actually be held.
Yes, people's own lack of diligence or awareness opens up possibilities anyway, but that's their choice. They could have things quite secure if they wanted to.
Anyway, the FBI wants Apple to build a machine capable of making a hole through that super wall - ostensibly because Apple is the only one that knows how to build such a machine. And the FBI says this is safe to do because Apple can make the machine such that it would only work on one such wall, the one protecting this particular phone. Also, this machine will never fall into the wrong hands - and, it having been built once won't make it such that others can figure out how to build it. I think the FBI is simply wrong on both of those fronts. And that doesn't even get at the problems with accepting that the government has the legal authority to order someone to do something like this, to build such a special machine.
EDIT: To add a TL;DR... Yes, it is possible that it's not the end of the world if this particular piece of ground is given up. But the reason this particular piece of ground must be depended is that, it is the only piece of ground between here and everyone that matters that can actually be defended. And that's apparent to those that understand the landscape. If we try to fall back and protect ourselves at different places, taking to arms only when our enemies are known and their victories imminent, we will have already lost. There's one place where we have a chance to hold a line that will meaningfully protect us. And it's right here, it's in refusing to allow this particular Rubicon to be crossed.
