Even if I plan to apply for a 2–3 month extension, do I need to book an outbound flight within the first 30 days?

Yes. Either buy a refundable outbound ticket, or use a booking service that issues a temporary ticket and cancels it automatically after you arrive, for a small fee.

It looks like you checked and got an answer that doesn't make sense, so you're checking again here. Welcome to the Philippines lol. Get used to things that don't make sense.

Yes, to be safe, have an outbound ticket leaving within 30 days. When boarding an international flight at your departure airport, the airline is the one that asks most often for proof of an exit within 30 days. Without proof, the airline won't let you board. If you bring someone in without an outbound ticket, the Philippine government fines the airline. The airline then gets stuck holding them at the Philippine airport and sends them home on that airline. At Philippine immigration, I was asked for proof only once in 50 entries. They often ask how long you're staying, and I just say 30 days. Use onwardticket.com. Basically it rents you an outbound ticket for $16 USD. The ticket is valid for two days, so book it right before you leave. If the airline or Philippine immigration wants to check, they can look up the ticket number in the system. I print a paper copy just in case. Set it up as a trip from Manila to somewhere like Thailand, leaving within 30 days. Public caution: I may not be supposed to say this about onwardticket.com, but as a warning to others: I used my real credit card number on that site, and twice fraudulent charges started showing up around the time I arrived in the Philippines. I can't say for sure it was the site's fault, but I'm suspicious. Since then I've used PayPal with the seller, which doesn't show the card number, and I've had no problems.

I have no idea. If the Vancouver Philippine consulate said it's required, then it's required.