There absolutely are cameras recording the entire airport surface. The people in charge of them don't usually have "I should post this to the internet" as their first thought. Some airports do stream them though.
It's like that footage you see of crowds of people standing around videoing someone in trouble rather than actually attempting to help or even use that phone to call for help. Nope. Gotta get those hits on their social is their primary function. I don't care if you think someone else has already called for help, make the damn call. If it was you that needed the help, what would you want someone else to do for you?
There often are surveillance cameras on the tarmac. I’ve been involved in many airport surveillance projects with cameras covering the perimeters and operations areas. They just might not want to publicize the camera coverages.
Runway conditions and landing conditions are not the same. The landing conditions were challenging. The runway conditions were considered dry. This is in contrast to various comments, including in here, bizarrely claiming that the runway had inches of "packed snow" and so on, apparently based upon a final crash scene that wasn't actually on the runway.
You said "I've not seen any video of the crash. Usually, when there's a crash, dash cam or other amatuer video caught it.". This is video of the crash. What's the problem?
Airports have cameras of course, though they have no obligation or value in providing it to placate social medias rush for content.
It's a tower video, but we also see the operator moving the camera to catch it. I would expect to see cameras passively covering the entire runway, and not needing an operator to frame it. The reason is the operator may miss something else happening, or may be distracted at the critical moment.
It also just takes time for those videos to get uploaded and spread. We already have 2 good videos from the approach end of the runway; one released by TMZ from a CCTV camera and one from a pilot waiting for their turn to take off.
If SpaceX can put rockets that produce live feeds of a craft re-entering the atmosphere, we should definitely have dashcams in every cockpit. Wing/tail tips would be cool too even if just to have those seatback screens have actual images. Then again, we still can't definitively say what happened to MH370.
It's also been snowing in Toronto all day with high winds and heavy snow squals. If you were standing in the huge pile of snow outside with a camera you probably wouldn't have seen it.
Which leads to my repeated bafflement as to why there are no video cameras constantly pointed at flight ops at the airport.
If every 7-11 can have a security cam recording hi-def 24/7, why can't a couple of these be mounted in the tower pointed at the tarmac?