If you want them to exist you they can't just ignore all finances. USPS had a break even mandate from 1970-2006. They projected revenue and priced services to break even. That was scrapped in 2006 and they had a price cap put on services which now puts everything into jeopardy. They havent been break even since.
Their core business has been declining for the past 20 years and business mailer lobbyists work very hard to keep the current price caps. This idea that we should let the finances spin out of control and raise taxes is a recent idea.