I can only agree.

I used it in 2013 when the Piccadilly line was closed over a week-end. I eventually found a website (forgotten where now) to buy an advance ticket.

The trouble getting a ticket was only part of the problem. I couldn't find the platform at Paddington. It wasn't sign posted and I couldn't find any displays. In contrast, you can't miss the expensive Heathrow Express for all the signs.

Eventually I found the platform hidden away on the extreme right of the station and seemingly hidden around a corner.

I think a lot of people who work at Heathrow use it in preference to the slow tube and the costly Heathrow Express.