Well, you can save money, although you must budget for other expenses. Anytime you leave the ship, you'll probably spend money. If you have "down time" between cruises, you'll have to spend money. Wi-fi can be limited; cell coverage is considered international roaming, so you need to decide how to handle it.
I don't believe Princess Cruises, or any other cruise line, will take you - or allow you to cruise - if/when you need Skilled Care Nursing. They are simply not set up for it. There's a reason why it currently costs $10-15K/monthly for SCN and Memory Care; it's intensive and requires licensed staff.
Cruise line medical staff are like Rite-Aid and Walgreen's clinics. Not all their doctors are trained in emergency medicine (it's not legally required, depending on where the line is based). They treat common ailments, and equipment is typically limited to ventilators and small X-ray machines. They may also have electrocardiograph machines, lab equipment, and pulse oximetry. They cannot do MRIs, and stock only a few of the most common prescription drugs. Specialized drugs are not available nor prescribed.
The majority of articles on this hotly contested issue point out that medical care is LIMITED on cruise ships, and anything truly serious - critical trauma, cancer, etc. - will cost a seriously high price. This can include being airlifted off a cruise ship (figure on average about $25K), assuming it is within reasonable reach from land. Cruise ships should be considered Independent Living. They are not suitable for, nor can they do, medication management, physical therapy and rehab, nor memory care management.
The cruise line can, and will, decline you as a passenger if your health changes substantially or you develop a serious disability. Ship cabins - the affordable ones - are not designed for walkers, let alone wheelchairs. If a medical emergency forces you to leave the ship, you will not receive a refund, as you 'voluntarily left' the remainder of your cruise.
Medicare will not cover you if you are outside US territory. You MUST have health insurance (some cruise lines will sell it to 'permanent cruisers'). You are still responsible for all state and federal income taxes on your annual IRS filing. You should also investigate the residency laws of your state.
Some cruise lines are focusing on the seniors who want to cruise permanently, but most do not. Those lines that sell permanent cabins are priced like condos, so instead of additional HOA fees you will pay ship maintenance fees.
I think if you're an extrovert and enjoy meeting new people, shipboard activities & shows, eating buffet food, having a 250 sq.ft. cabin with a tiny window that you have to leave (so they can do housekeeping) once daily, it's an alternative for a limited period - the "active phase" - of your retirement.
And no, they DO NOT dump you over the side 'at no charge' if you die. That is a serious violation of maritime law for a cruise line.
