Here in the UK they died out about 20 years ago when our Data Protection Act came in to force and stated companies could only call people who had given them prior permission. Calls still happen (either illegally from UK companies or from overseas companies to whom the UK law doesn't apply) but they're much less common.

Naw, they never died out at all. We used to get bombarded with international calls prior to blocking international calls. Now, they just spoof them from an adjacent city - we've had them purportedly from Liverpool and Bristol. Bizarre, but still happening.

American consumerism, access to easy credit, lower financial education, etc..

The U.S. has more rich suckers to prey on.

At first glance this comment might seem shallow, but I think we can unpack it a bit.

1. It’s probably correct? The US is a very large single market

2. From some quarters the US does come across as being fairly laissez-faire

3. The scale of predatory economic activity in an otherwise highly developed economy is(?) unmatched

4. Penalties seem to be a cost of business rather than genuine attempts at deterrent

5. The general appearance of a lack of accountability

But, I’m just looking on from afar, and I’m sure the media advances the hyperbole.

Because unsolicited calls are not legal in other countries

They're often not legal in the US either, but it isn't enforced. It has more to do with enforcement than it does legality.