No don't be. I enjoyed the Top Gear segment as much as I did the movie. Which is amazing considering it was a small segment vs. a full length feature film. Top Gear had hero's like Hamilton, Hakkinen, and Schumacher testifying to his greatness which carried a lot of weight. The movie didn't play up his greatness as much. Possibly because of Japanese humility. Though there was a eerie foreshadowing clip of Ratzenberger commenting on how Senna drove on the edge. From the day Ratzenberger was killed.
I was disappointed the movie didn't show that clip of Senna stopping his car to check on the other driver who had crashed until after the movie when the credits were rolling. To me that said a lot about him as a person.
After seeing Senna run Prost off the road in the Top Gear bit I thought it was pretty unsportsmanlike like. But after seeing the full backstory in the movie I felt like cheering when it was shown. You could still tell Senna was torn up about it though.
For worldwide release they'll have to do new English subtitles for all the Portuguese clips and interviews. There was a lot of focus on Suzuka but that's to be expected since it was the final race of the season back then so I don't think they'll change that. There are some clips and interviews with Japanese reporters that they might shorten or take out.
It's very much a documentary so it won't be a big box office draw outside of Japan and Brazil but if it does get a theatrical release near you I'd definitely check it out. Again, the sound of that MP4-4 was incredible and frankly makes modern F1 cars sound sterile and a little boring.