In act 5, What do you think of the play's ending? Is it satisfying or diappointing, effective or otherwise?
As a question of personal perspective any opinion might be suitable, however, one must analyze a number of hidden elements that transpire in Act V of GB Shaw's Pygmalion.
Act V, the final act, brings with it a series of things that were not dealt with before in the play. One of these things is Eliza's contained anger and resentment against Higgins. Although Eliza is a strong woman from beginning to end, at no time have we witnessed her so truly rebellious and extremely angry. She faces Higgins with such firmness that we must question whether her feelings come from true ire or from feeling unappreciated from a man to whom, deep inside, she feels indebted to. However, since he is not worthy of her, Eliza takes an unprecedented step towards female self-assurance and self affirmation by telling him like it really is:
Aha! Now I know how to deal with you. What a fool I was not to think of it before! You can't take away the knowledge you gave me. You said I had a finer ear than you. And I can be civil and kind to people, which is more than you can. Aha! That's done you, Henry Higgins, it has. Now I don't care that [snapping her fingers]for your bullying and your big talk. I'll advertise it in the papers that your duchess is only a flower girl that you taught, and that she'll teach anybody to be a duchess just the same in six months for a thousand guineas. Oh, when I think of myself crawling under your feet and being trampled on and called names, when all the time I had only to lift up my finger to be as good as you, I could just kick myself.
Secondly, we also witness Henry's own fit of flagrant rage and fury that goes to the point of really offending Eliza like perhaps no other character has offended a lady in this genre:
You damned impudent slut, you! But it's better than snivelling; better than fetching slippers and finding spectacles, isn't it? [Rising] By George, Eliza, I said I'd make a woman of you; and I have. I like you this way.
In the end Eliza marries Freddy but the two end up still connected to Col. Pickering and Higgins. There is no ultra special change in anybody, nor is there a miracle solution to anyone's problem. This is the romantic period; the reality genre. All things are meant to be the way they would be in real life. Hence, as per the characteristics of the genre, nothing out of the ordinary is supposed to happen in the end.
We could agree that, since this is the ultimate purpose of the author, the play then follows quite rigidly the checklist of its genre and serves as a great example of it. One almost wonders where is that kiss between Eliza and Higgins, or when will she leave Freddy...but nothing of the kind will take place. Therefore, it is up to the audience to choose between from and philosophy to decide whether they enjoyed the ending or not.