To some extent you are right. Many folks simply give up because of either the cost or the paperwork involved. Statistically, there seems to be a very good chance of getting certified. However, it's a bit like weight loss. It's easy perhaps to lose weight, but keeping it off is harder.
The issue with the tests is that the FAA asks for certain tests that are not normally considered required by the mainstream medical community. So your doctor will oblige you with the order but the insurance company will not pay for it, especially if the interval is short.
As an example. The FAA requires a angiogram (very invasive) 6 months after bypass surgery. It can cost several thousand dollars depending on where you have it done. Most cardiologists will wonder why you need one six months after surgery. But if you don't get it you are dead in the water for an FAA medical. Then they require a Bruce Protocol Stress Test every year and a Nuclear Stress test every two years, in addition to full blood and lipid profiles. So as you can see these can really add up. If the test is not done to their specifications (VERY VERY IMPORTANT) they will reject it and it has to be redone.
It can be done if you have the patience, determination and ofcourse the funds. I suggest you give it a good try with an initial consult and then decide further. Best of luck.