I adored season 1. Incredibly insightful, well-plotted, narratively-tight, absolutely beautifully filmed, and insanely well-acted (apart from the character of Nick who is the weak link). Season 2 was enjoyable for me too; it really dug into the meat of the main characters, especially June's foil, Serena, and developed the dynamics of all women (not just June anymore) and how they survive under the regime. It seemed like the show was going somewhere interesting.
Season 3 was where it started to fall apart. It was tolerable in the first half, and just ridiculous in the second half. Some amazing scenes from the two main actresses with each other. It really should have just ended after S3. (If not one of the previous seasons.) But it became very one-note.
Seasons 4, 5, and 6 are pointless and repetitive and downright awful. There is no reason for any of them to be made, or watched. They say nothing, do nothing, and none of the magic from the first 2 seasons is present at all. The plots are laughably bad and completely unrealistic, clearly the writing team did no research. None of the characters are likeable at all, not even the protagonist even when you consider her trauma. They separated all the characters (especially the key dynamic of June vs. Serena) from each other and the conflict is tediously flat and melodramatic enough to rival the worst soap opera. There's no tension because by now you know June is going to be fine. She can't die! She will never die. And neither will her similar plot-armored husband or one remaining named Handmaid, Janine, or Evil Aunt Lydia. There's no tension because none of these people are ever actually in danger despite the fact realistically they all would be killed years ago. As the series progresses they give more and more screentime to male characters and sideline female ones, and it starts to become The Handmaid and All Her Men's Tale, instead of hers. Focusing on love triangles and which man does June love, promoting some #notallmen IN AN OPPRESSIVE REGIME silliness, and being more concerned about which men are "good men" and which ones are bad. Oh, and the idea that all women need to be happy is babies, all women are obsessed with babies, and babies make childless women inherently better people. That's a fun message for a show like this. It's a very typical, out of touch Hollywood approach to civil rights and feminism.
They are empty years of a once amazing show and barely worth the electricity used to power up the TV screen to watch them.
Pretend the show ends at S3, or S2, and you'll probably think it was awesome. Keep going, and you'll regret it.