Good advice.

I fly Delta mostly to Cancun. In twenty plus trips we have needed from 20 minutes to 1h40 to get to an international gate. The priority lines can be long and slow moving. I always leave hotel 3 hours early if I can. The international departure area is very adequate and there is a business (priority pass member) lounge that anyone can use for I believe $25.

That said we fly out on the Saturday after Christmas or New Years. Saturdays have the biggest crowds and these are two of the busiest days. Mid-week or other times, I'd be tempted to leave 2.5 hours early for the airport (20 minute ride for me). Others wait until the last minute. I've seen some really panicked people begging to jump the waiting line.