Vancouver will never reach megacity status... Because at just under 700k in the city limits, and just over 2.65M people in the CMA/Metro it's been prohibitively expensive for decades.
It doesn't have a robust economy like the Bay Area or something. It's become a place for foreign nationals (particularly Hong Kong and now mainland Chinese) to park their money in real estate drastically causing the price of real estate to rise for everyone else.
Home Price Index composite benchmark price
$
1,210,700 or $895,000 USD
This is almost double the Canadian benchmark home price.
Single detached home benchmark price
$
2,012,900 or $1,500,000 USD
Attached home (semi, townhouse) benchmark price
$
1,104,600 or ~$820,000 USD
Apartment/condo benchmark price
$
771,600 or ~$570,000 USD
CREA stats from the Real Estate board of Greater Vancouver
https://creastats.crea.ca/board/vanc