The thing is, it's usually true. Even when it's not hard it's often complicated - just think about climate change over the last several decades, for example. I don't envy politicians, who have to keep everyone distracted and happy while their staffers do the real work. They seem to enjoy the gig though.
Here's the thing... If there's an easy answer we've already done it. Sometimes an answer is hard because of trade-offs or technical requirements... Sometimes it's just hard because of conflicting interests and lobbying. But, if it's easy, we do it... No politician ever is allergic to easy wins.
That all said, if you have a good idea, especially at a local level, don't blindly assume it's been thought of and rejected already.
There's simple answers, but no one wants to hear them because they're politically complicated:
We treat housing like an investment
We have a tax code that's excessively friendly to investment income, so we encourage the problem even more.
We're unwilling to tax rich investors to pay for the gap in housing availability
The CMHC gave up on directly building housing at scale 30 years ago, and successive neoliberal governments at every level have no appetite to do publicly-provided anything, let alone healthcare.
Housing, like healthcare, is a market failure, and our governments are still looking for market-based solutions which won't work as long as the market can make money off the problem's continued existence.
The "no simple answer" part gets worse every day, because the longer governments wait to intervene, the more of our economy gets tied to real estate. This could have been fixed in 2000 without too much pain, but now you'd be tanking the only retirement savings many Boomers and elder Xers have, so actions need to be gradual: a gradual clamp-down on investment, and a gradual ramp-up of direct building of housing.
Of course, what we're going to do is "more nothing" because even gradual moves will be fought tooth and nail by the rich. So they kick it down the curb another four years every time.
We also aren't willing to admit that the majority of the housing we build is economically unsustainable. Most suburban developmemts cost more to maintain than they generate in tax revenue. Once the developer's initial payments are spent, suburbs just start bleeding money on infrastructure maintaince.
This is of course amplified by the housing as an investment problem as higher density projects could lower property values in the short term and NIMBYism flourishes when we treat housing as an investment.
Most suburban developmemts cost more to maintain than they generate in tax revenue
Ah, another easy solution: raise taxes to pay for stuff.
It's amazing how that works for just about everything that's broken in our society: Doctors and nurses quitting in a droves? Raise taxes to pay for them. Education system failing? Raise taxes. Housing unaffordable? Raise taxes.
You'd think we'd just raise taxes to pay for stuff, especially since cutting taxes since 1980 is why we can't afford to pay for stuff. I thought right-wingers were "good with money", but they don't seem to understand that "you need money to pay for stuff".
Maybe if I talked about it like a family budget, the way right-wing politicians do: you make $100K a year, and have $90K in expenses. Do you try to get a raise, or do you decide to take a $30K pay cut so that your boss can buy an extra yatcht and...trickle down..mumble..mumble.
Those are answers that don't factor in immigration at all. And are still deceptively complicated.
Housing is an investment, just as much as the foundry that makes the front doorknob. Both are critical to our standard of living, but both also cost a lot of money to put in place. Somebody will have to pay to build more. That could be the government, like you're saying, or it could be developers who are looking to cache in on the high prices and therefor bring them down. Which one should do it is complicated.
Ah, but who will build it? Obviously not immigrants. What if you build housing, but then they can't afford it? What if they're underhoused where they came from, too? And then of course, if we don't take in immigrants and the economy goes in the toilet, all the housing there is might get pretty run down for the elderly Canadians still left.
If you actually read the article, you'll see several examples of how it's complex.
We could've spent 2-3 years heavily investing in housing developments before ramping up our immigration and then keep those developments coming until immigration slowed down or demand is exceeded.