As situations become harder to imagine in an tangible sense it becomes harder extrapolate from intuitions meaningfully. But I can give some response in this case.

I then at T2 convert W2 into a chunk of pure orgasmium (O).

If I've understood your view, you would say that at T2, W1 undergoes a utility change (equal to [value(W2) - value(O)]), though of course W1 is unaware of the fact. Yes?

Utility functions operate over entire configuration states of the universe - values of objects or beings in the universe can not by default be added or subtracted. Crudely speaking W1 undergoes a utility change of value(universe has W1, O) - value(universe has W1, W2). The change would be significant - clones have value. And this is the first clone. Transforming a hypothetical W534 into orgasmium would be a far, far lesser loss.

Whereas in an alternative scenario where at T2 I create a chunk of orgasmium (O2) out of interstellar hydrogen, without copying you first, W1 (which is uniquely you) doesn't experience any utility change at all at T2. Yes?

It is worth elaborating here that the states of the universe that utility is evaluated on are timeless. The entire wave equation gets thrown in, not just a state at a specific time. This means [W1, hydrogen -> W1, W2 -> W1, O] can be preferred over [W1, hydrogen -> W1, O], or anti-preferred as appropriate without it being an exceptional case. This is matches the intuitions most people have in everyday use - it just formulates it coherently.

In this case W1 does not seem to care all that much about what happened at T2. Maybe a little. Orgasmium sounds kind of more interesting to have around than hydrogen.

Also note that the transition at T1 leaves W2's utility function at a high percentage of W1's - although W2 definitely doesn't know about it!