It's a pretty extensive system and the pretty new Elizabeth Line is great. But if you take something like the Piccadilly Line in from the airport, you probably shouldn't have a lot of luggage because a lot of stations just have stairs and platforms are often at a significant offset from the underground cars. (The double decker busses also work pretty well although they're not generally my default.)
Other way round is my understanding. Road based transport was for the poor, especially trams, and the underground was for the fancy folk looking to shortcut past all of that.
> a lot of stations just have stairs
Very few, if any. They may not have escalators (Covent garden, for eg., but no-one in their right mind uses that - just use Leicester Square and walk on the street) but there are almost always ways of getting up to the street, and assistance is signposted for people with problems.
> platforms are often at a significant offset from the underground cars
Not sure what you mean here - mind the gap? Typically less on the Piccadilly than some other lines - Bank on the Central is particularly scary.
Based on living 30-odd years in London, most of it using the Piccadilly line on my daily commute and to get to LHR.
Sounding like a TfL groupie here, but it is a pretty good transit system, given geographic and budgetary constraints.
It's not just the gap. The platform can also be a somewhat significant step up from the car. Normally not a big deal but a couple years back I had both real dress clothing and clothes for a long walk in my luggage on a fairly long trip overall.
Agree that the Underground is good in general. I've used it a lot. That particular trip was just a case of having heavier luggage than I usually carry and I should have handled things differently.
The Piccadilly Line was opened in 1906 for gods sake, forgive them for not catering to people with 3 suitcases very well! That's part of the reason we built the Elizabeth Line, to enable a better transport option for people coming into heathrow.