Roads do get a beating because of snow. Montreal definitely get more than Toronto, and the road system is way over capacity, with the number of cars and trucks increasing 2% each year.
The costs estimates are interesting too, because the construction industry is/was colliding in order to hike prices. So now all projects are fixed-price, meaning that companies won't take risks and tripple their estimates.
Some say that these problems started in the 60s, but got worse during government downsizing attempts. Internal expertise was lost and they had to rely on (corrupt) private companies. Others say that the restructuring were required to get rid of inside corruption. Whenever two government entities get merged, it's pretty much always as an attempt to water down corruption.
All that said, these days the city is pretty lean. I know lots of folks working there. I also did my small part to help liberate the city from Oracle consultants (siphoning the city) and also ran for borough office some time ago.
Just don't get your car towed. They are as bad in Montreal as everywhere else. And the city needs more public transport.
The other factor is repairs were neglected for much of the 2010s, which compounded damage, so they're playing catch-up. So yes, there is a lot of construction, and undoubtedly some corruption and incompetence mixed in, but it's not as bad as some people who like to complain say.
It will be interesting to see if they can "catch up" some year, and it's very important for informed people to remain critical and engaged.
A lot of new modern buildings have been erected downtown and the city is quite clean.
As for the corruption, it is very visible on the roads. They are constantly redoing the roads and yet there are still a lot of potholes. The weather is not an excuse, roads are much better in Ontario.
Also I don't know if it is still the case but you could read occasionally in the news some housing construction buildings being burnt.