I think this movie has its positives and is definitely watchable, but looking back it has aged pretty terribly. The acting is so over the top and the direction is overly sentimental. I don't think it would be nominated for Best Picture if it came out today.
Jack is great fun in this thoroughly enjoyable film and he did give a good speech but he could have given this performance in his sleep. I think the best of the nominees was Peter Fonda, and there were some non-nominated performances I preferred, too (Ian Holm in The Sweet Hereafter was probably my favourite eligible performance of the year).
I do think the film would quite likely be nominated today - it received good reviews, was a big hit and James L. Brooks is a pretty well-respected writer-director.
The acting was no less "over the top" in 1997. It was never meant to be realistic. It was like a modern throwback to the old Grant/Bergman (or Hepburn) comedies.