Was Hitler objectively bad?

[theVOID]

This is rooted in the same false objection answered above. Even if you don't want to call it morality, you can be objectively wrong in thinking that desire x will be the one that brings about a state of affairs in which more and stronger desires are fulfilled. It may be that you think keeping slaves will bring about a better state of affairs, in which case you are objectively wrong. You may think voting for party y will bring about a better state of affairs where it turns out to be wrong

Using a methodology for evaluating desires we can be more accurate in determining which desires tend to lead to a better state of affairs.

I would argue that this is very much morality, but whether you want to call it that or not desires exist and are the only reasons for action that exist, and there is an objectively true or false standard by which we can judge desires by their tenancy to bring about a state of affairs in which more and stronger desires are promoted vs thwarted.

It's true that we can objectively assess what will promote the fulfilment of most desires, and that desires are the only reason for action that exist. You still have to bridge the is-ought gap by explaining why we should desire things that fufill others' desires, rather than just our own.

Look at an example, propose your own if you like.

1. We desire not to have things stolen.
2. Theft is an action that tends to thwart more and stronger desires than it promotes.
3. A desire is a brain state that produces a conceptual future in which a proposition is true or false, we always act as to fulfill the strongest desire we have from a set of conflicting desires (Empirically supported)
4. We have beliefs about a set of facts that can be used to determine which action will help fulfill the desires in question. (Empirically supported)
5. Desires are the only reasons for action that exist (Empirically supported)
6. We have reason for action to promote a diversion to theft as it is a desire that tends to thwart more and stronger desires than it promotes in ourselves and, coincidentally, others.
7. These actions can be assigned a positive or negative value depending on their tendency towards a state of affairs in which more and stronger desires are promoted than thwarted.

If you agree with that the argument shifts to why we should use the label Morality.

'Ought' only makes sense within the context of a hypothetical sentence like 'If you want to succeed, you ought to study hard'. Of course, you could say, as you have, that desirism succeeds if we wish to promote others' desires, but there is no objective reason for us to want to do so.

No moral system is supposed to make you moral, which is what you seem to be wanting, it is supposed to describe right and wrong conduct. You will not act to fulfill a state of affairs in which more and stronger desires are fulfilled than promoted unless you value such a state of affairs. I argue that Desirism best describes how we determine what actions have positive or negative value based on their tendency to this state of affairs and that the framework constructed is the best description of morality we have on the grounds that it 1) Makes perfect use of moral language 2) Provides reasons for action that actually exist (unlike any other form of moral realism) 3) Is in line with the vast majority of non-doctrinal moral intuitions (or opinions) in the vast majority of circumstances, suggesting that the value based relationship between actions and the consequences is something we've been doing all along anyway without a solid concept of it.

What Desirism gives on top of that is a methodology that can objectively determine which desires are in fact the ones that achieve a state of affairs in which more and stronger desires are promoted (fuck I need an abbreviation for that) and which are not, and these can be given a positive or negative value, and thus the label moral good and moral bad, depending on their ability to promote the state of affairs.

If you have a better explanation for morality, or a good reason why Desirism does not accurately and best describe all of those moral criteria that are relevant in our use of the definition the i'd like to hear it, otherwise Desirism is the most accurate description we have of all of these moral phenomenon and as such if you value having beliefs that are consistent with the best descriptions of events and value a state of affairs in which more desires are fulfilled than thwarted you have good reason to act according to this framework, whether or not you want to call it Morality.

Thus, I can't see how desirism solves any problems that are not solved by, say, preference utilitarianism, which is similar to desirism in its normative prescriptions, but doesn't claim to solve any meta-ethical difficulties.

Which problems do you specifically have? Examples would be nice.