There will be modifications to road laws to take account of that. While it does stay in the body for a lot longer which is why the prison drug tests have seen far more serious drug usage in prisons as inmates switch to a drug that is not detected after three days rather than the 6 months that cannabis stays in the hair. That was widely predicted before the introduction of the prison testing regime.

I do not necessarily think that it will make people less safe more than a day after usage.

I lost a good friend from uni who had got good grades at school and made it to a through the first 2 years of a really demanding degree until he started abusing. He had to be sectioned after weed destroyed his brain and he dropped out. This was 7 years ago and as far as I'm aware he's never been out of the psychiatric ward. So it's definitely not a safe or "mild" product and it is very addictive.
However I guess one can't stop drugs being dealt, so why not get a tax income from it and control the quality and potency of the product?

The problems are down to skunk. I know users who have smoked weed for decades without problems. One deal did tell me that there were problematic users who sought out the strongest versions of skunk, which definitely creates problems. Skunk and cannabis are not the same.

He was smoking the stuff you get in Holland over the counter, not some backstreet deals. Cannabis is dangerous.

There are a percentage of people who do get problems. Though alcohol has its problem users as well. Also I think that you can buy Skunk in the Amsterdam cafes.