If any analytic philosophers suppose that deductions with actual content can be made from pure formalities then they do not practice what they preach. They are in effect doing speculative philosophy if they attempt to do this. [In contrast with Hegel, I would see this implicit speculative content as a flaw rather than a virtue.]
But in anycase it is important not to mystify Hegel or to see him as standing opposed to this or that strain of philosophy. He saw himself as integrating philosophy not dividing it into immutable 'Anglo-American' strains and non-'Anglo-American' strains.
Oh, he speaks of the English utter misconceptions of what Philosophy is all about, how they smuggle stuff they allegedly go against, under the table and so on - just read his account of Bacon and co.... So, he does make this distinction by
de facto developers of such a strand of thinking, which prevailed there, in those Philosophically poor parts of the world, back then... Btw, they still are, in more ways than one, sadly... People like A8, Phil and so on are an utter rarity... and attacks on speculative Philosophy are more than common place - they are the norm, as we can see...
If I could say succinctly where I think Marcuse is confused is that he sees speculative thought arising from the active engagement of the thinking subject. He sees it as mere reflection as Hegel would put it. Hegel's speculative philosophy is not a product of pure thought as an activity (the word 'speculative' is very misleading, it isn't meant as some sort of guess at how things are) but rather it is logical in that it describes the necessary forms through which thought must pass.
Is it? It is, almost literally, starting from the Whole, as opposed to the position that starts with elements, with "experience", with "sensations" etc. but accounting for and placing all other developements and positions into the development of Human Spirit. Again, read his account on Bacon and Newton and so on on get educated on the subject... In other words, Hegel knows and accounts for other possible approaches but in his opinion, following Kant, Fichte and Schelling...
Of course the speculative in Hegel is not a product of romanticism, its a product of religion. It is about knowledge of the infinite rather than the mere finite. Again this is something that Marcuse seems to miss. Mind you I haven't read much Marcuse, just enough to know that he isn't worth bothering with on this.
No, it isn't. It is the product of Humanity's/Subject's self-activity which happens in History and of which religion is but a part - but even that, however important, is given any meaning by Philosophy, which gives it its place in the Universal, Geist, Whole, Spirit, the Absolute etc.
The whole point is to show all the inner contradictions resolved as Subject's coming back to itself [via labour of notion and notion of labour], whereby the Subject/Geist recognises itself externalised and "reposesses" that which is essentially spiritual, i.e. belonging to Spirit, i.e. itself, i.e. its own product...