I agree - the role of the consulate is to advise and maybe assist Britons overseas (depending on what the issue is.
So yes, they're the first port of call for emergency travel documents if your passport is lost/stolen
If you are arrested, they can check you are being treated normally in accordance with the laws of the country, can explain the key points of the legal system, signpost suitable lawyers and interpreters and may talk to the local authorities if there are significant differences to the country's normal standards. They cannot intervene to get you more favourable treatment (in the judicial process or during imprisonment) nor can they arrange repatriation under any terms other than those of international prisoner exchange agreements.
If you are a dual national, you are in the country of your other nationality and that country does not recognise second nationalities for its citizens, you may not get ant help at all - not because the British authorities are unwilling, but because the local authorities simply don't permit it.
They cannot pay for stuff for you - better to get on to your bank or have someone use Western Union to transfer funds if you are stuck. Slightly different if in a crisis situation - but you'll still need to sign a binding agreement to repay.
They also deal with paperwork and some practical aspects of births marriages and deaths abroad. Plus playing a role if there is a kidnapping or hostage situation, and in some circumstances offering victim support.
They also assist in averting/escaping forced marriages, can help if someone goes missing abroad, and deal with international child abduction cases.
What they are not is some sort of catch-all/holiday rep/saviour. You can get a range of services, but you need to pay for nearly all of them, and also it's worth being aware that some of these are signposting the relevant local services and then expecting you to get on with it