In 2028, there will be strong indicators of continued climate change. But denialists will be able to say "well we can't say for sure, there's this huge gap in data from 2016-2024, we need to have at least 16 years of solid data in order to say for sure."
[0]: https://www.google.com/amp/s/www.newsweek.com/how-long-all-f...
If you think there won't be, I'd say you're far too optimistic.
But I think a bigger issue is that we're going to spend 4-8 years making little progress actually fixing climate change. Any changes we do have greater impact the earlier we do them. It was a smoldering fire in a wastepaper basket 30 years ago. Now one bedroom is on fire. We're going to spend another 2-6 years doing nothing while the fire continues to spread. Hopefully we'll still be able to put it out once we get an adult into office.
I think that's the biggest issue.