Regarding cost of living, it depends where you live in Israel and where you live in the U.S. Tel Aviv is way more expensive than Houston and less expensive than New York City. That's the most expensive place in Israel. If you can live in the Negev or in the Galillee there may be additional incentives offered by the Israeli government when you make aliya and the cost of living will be much lower. In addition, tax rates vary from state to state and even city to city in the U.S. That tax rates will be higher is also not a given.

The real issue for North American Jews is that wages are significantly lower in Israel. In my field, with a skill set that is in very high demand in the U.S., I would have to take a minimum of a 2/3 cut in pay if I made aliya now. That's why I must first be debt free and then have a substantial savings ready. Many people who are comfortable and don't feel threatened are not likely to make aliya under any circumstances for purely financial reasons. Most Americans and Canadians don't have the level of attachment to Israel I have, such as family ties.

In places like Yemen and Iran the Jewish population has no choice. They are not permitted to leave and it is extremely dangerous to try. In the case of Yemen there was a recent article about Israeli government efforts to help that population escape.