Where are you getting these numbers from? Both are pretty big departures from published TTC materials. 2031 demand for Yonge is about 36,000 pphpd while DRL predictions are well under 20,000. Considering it will have taken Yonge nearly a century to get to this point, you're assuming a lot of induced demand.
TTC has numbers right for 2030. My estimate was for closer to 2045 (opening day + 20 years). I do not believe DRL will be funded even for engineering work before the next provincial election.
Many GTA office managers are already torn on where to expand because of the difficulty in getting employees to any location in the GTA. GO trains are full, TTC is full, highways are full both in the suburbs and downtown. Downtown wins because everybody is punished equally and employees like it. Based on what is under construction today, this situation will be much worse in 2020; not better.
Any new transportation corridor (highway, train, whatever) will spur significant commercial growth around it simply because workers will be able to get to that location. Downtown especially if it's still the popular place to be.
DRL East opening day + 2 years of nice subway commutes + 2 years to decide on an office expansion + 5 years to lease, design and build a new tower. After 3 cycles of office development (~18 years) the DRL and Yonge will both be approaching capacity UNLESS additional significant transportation corridors are also created in the GTA.
Our recent history and continued funding issues make it unlikely to see significant gains in transportation aside from a DRL and minimal GO service bumps by 2045 so many new downtown workers will be arriving by subway. GO will continue to boost service after it's shown to be necessary, just as they have for the last several decades.
You've criticized others for making up numbers...
Yup. Didn't mean to imply it was anything but pure speculation. I expressed personal confidence in a number I put forward. I did not imply it was of equal or better weighting than anybody else's speculative statement or that the numbers another agency produced were incorrect (I'm not aware of recent TTC/Metrolinx numbers past 2031).
Also, it's so far to the future I don't see how anyone could act financially on my opinion so I didn't add a disclaimer; although I have no intention to buy or sell real-estate in downtown Toronto over the next 3 months.
Also, to be specific, I've criticized others for making up numbers that directly conflict official information. The real issue is that 2 years later those same people are presenting the same arguments which a number of others have shown to be faulty. I wouldn't mind so much if they were new arguments or even just reworked with the information that they had been provided.
TTC compared their work with Madrid's in great detail. You can take issue with specific portions of that report but the time for jumping up and down about Madrid being cheaper and TTC not explaining why is done.