In 2025 I had 36 flights (segments) with AC, all were "on time" by my standard.

No misconnects.
No uncomfortably short connections
I got to everywhere I needed to be.
I did not miss any family events, games or meetings.

Some of this is by design on my part with allowing 3-4 hour connections when Dom-Intl, don't care how short Intl-Dom is and understanding how things work
When I take my regular trips to either AKL or LHR I understand that I will be on a machine consisting of ~2,000,000 parts, one or more of which could become inop at the most inop time.
A part may be able to fixed/replaced in minutes, but could take 24 hours.
When replaced/fixed, logbooks need to be undated and signed off.

The people flying the plane need to get to the airport to fly it, they can allow lots of time, but if the Sea to Sky (Whistler to Vancouver) closes in front of you become of some moron in their Lambo, not much can be done about that so flight ops triages it and then another flight maybe missing a pilot.
In bound flight with the DH'ing pilots needing to operate my flight may be delayed.
Same applies to the FA's.

The tug blows a hydraulic line, turbo fails.
Catering truck gets held up.
NavCan laid off a bunch of people during COVID, have they stoned that person yet? ATC staffing is a major issue.

It snows in Canada, also gets very cold, has lightening as well.
You can plow, push snow as much as you want but when it is blowing horizontally and swirling, may as well piss into the wind.

Airports themselves have a whole host of issues.

Based on my limited sampling, AC's OTP in 2025 was 100% as far as I'm concerned