I'm not going to say that I don't share that pilots frustrations with YVR. It is annoying to get a 40 minute ground delay going to YVR, to then take-off and suddenly get a 20 minute delaying vector or an instruction to slow to min clean speed for 100 miles. It's also annoying to get a 25 minute delay leaving YVR on an otherwise clear and a million day. It's almost a game between pilots and controllers at other airports regarding flow to YVR. But YVR has some unique airspace challenges with the mountains to the north and US airspace to the south, and a runway rehab project that, depending on the time of day, closes half the airports operating capacity. That rehab project started with the south end, and has now moved to the north end. From my understanding, NavCanada did have plans to restructure the airspace prior to COVID to allow a better flow of traffic and increase the ADR and AAR, but that was kiboshed. I've heard it is in the works to come back, but as with everything else, money talks.
However, the OT "issue" was never more than a rumour. As far as I know, there is no evidence for it, at least not in the way it is presented. Every single time another pilot tells me "100% it's an OT issue", it's always from a story told by a brothers friend's cousins sisters aunt who knows the sister of the wife of a controllers best friend. I find it's much more simple to believe that ATC is a hard job, that the attrition rate for new controllers is high, and that YVR is a very expensive place to live. Put all that together and it's easy to see how staffing in a major centre could be hard. According to NavCanada, a Tower controller starts at CAD$101,000 and an ACC controller at CAD $139,000. That's not a bad starting rate, but not once you factor in the municipal, provincial, and federal governments taking close to 50% of that in some form of tax. Then factor in that the average house price in YVR is CAD$1.1 million, and it's easy to see how younger people don't consider it enough money.
Also, one thing the story does not go on to say is that there were additional challenges throughout Canada in the last few weeks. I'm not sure what happened in Alberta, but there were 45-minute delays leaving YYC. The day I was working, no one was getting clearances above FL270 until they crossed into another ARTCC, which generally indicates someone called in sick and no one else has the qualifications or certifications to work that sector of airspace. So I find it entirely possible that this pilot was faced with a departure delay and an enroute delay, but was presenting it as a single issue because that's how it was presented to him.
Frustrating yes, but I'm not sure it is worth venting those frustrations to the cabin.