I don't think the ending was hamfisted.
I actually think it was a bold move to have Thanos win it all at the end.
And while, yes, I knew the deaths caused by the Finger Snap would be reversed, I look at it from the characters' perspectives. Seeing those around you disintegrate or being disintegrate yourself was still poignant unless you went full Comic Book Guy on the film.
I'll point out that the two that got me were Groot's (James Gunn said his last "I am Groot" was him saying "Dad..." to Rocket) and Spiderman's (seeing this teenager, just a boy really, knowing that he was about to disintegrate into dust and clinging to Stark for comfort).