What you "think" (if you can call it thinking) is irrelevant.
First, the £1.7 billion figure gets repeated endlessly, but it's gross economic activity, not a cheque written to the Treasury. The UK tourism industry is worth hundreds of billions. Tourists come for history, architecture, museums, culture and heritage sites. France attracts more tourists than Britain without a monarchy at all.
Second, "they bring in money" doesn't answer the criticism being made. Plenty of things generate revenue. That doesn't make them immune from scrutiny. If your entire defence boils down to "it makes money", you've abandoned the actual argument.
Third, dismissing everyone who disagrees with you as "unemployed pink-haired tosspots" is usually a sign that you've run out of facts. Plenty of republicans are taxpayers, professionals, business owners and employers. Inventing a cartoon version of your opponents doesn't strengthen your case; it advertises the weakness of it.
So far you've offered a dubious headline figure, a non-sequitur and an insult.
That's not an argument. That's a tantrum.