Stephen T’s review published on Letterboxd:
Thank all the stars, all the new additions to the cast can at least hold a tune. While Seyfried was already the best member of the original cast and therefore does the most singing out of all the returning members, Lily James is the best singer in both casts and has the most singing and that makes me happy.
That alone would be enough to make this an improvement over the dire original, but that's not all. We have a director who has actually seen films before, and therefore knows how to do things like place cameras in positions that give decent angles, and edit footage without relying heavily on slow motion. So there's that.
The bad stuff then. Most of the good singles were used already, so what we have are the B-sides, which aren't really ABBA's best stuff to begin with. And they're all shoved in incredibly inorganic ways (When I Kissed the Teacher suffers terribly from this.)
But worst of all, the whole The Godfather, Part II structure simply falls flat. The past and the present material never gel in ways that work and they transition poorly from one to the other in the first half (with the exception of I Have a Dream, which incidentally is the best number of the film.) This makes what should be a very short film feels incredibly padded and longer than it actually is. The ending for me didn't work at all, because it seemed like it's trying to convey A Lesson without actually saying what The Lesson is, and therefore my eyes remain stubbornly stone-dry.
But hey ho! A sequel that improves on the original! Except I can name at least two other sequels that also improve on the original playing in cinemas right now, but don't let that stop you from picking what's fun for you.