Because Putin and his Russian occupier troops and thugs have turned the once beautiful Crimea into a Russian thugocracy, kleptocracy, gulag hell-hole just like the "good old-bad-old days under Soviet rule for the overwhelming majority of people now trapped, living (if you can call it that) throughout the Crimean peninsula.
Russia has mined the land bridge connecting Crimea to mainland Ukraine and his thugs control who gets in and who gets out. As for tourism... it is all but dead and for those Ukrainians and others foolish enough to go to Crimea for "vacation" I will simply pass on the following told to me by a trusted believer I have known and worked with for over 25 years:
This summer some men from our church decided to go to Crimea for vacation as they had done many years before. All of their papers were in order and they were allowed over the border into Crimea. After they had spent a week they headed back home to Ukraine. Two miles from the border men with automatic weapons stopped their car and ordered them to get out of the car. They told them to hand over the keys to the car and were not allowed to take any of their valuables with them. The thieves gave them just enough money for third-class train tickets and told them to "leave and never come back to Crimea again!" They confirmed that the same thing was taking place against other tourists who were traveling by car on the only road out of Crimea.
Simply put; Putin and his Russian thug occupiers have utterly destroyed the Crimean tourist industry. Who in their right mind wants to go to Crimea to be brutalized and terrorized by heavily armed "little green men", Russian biker gangs, and Russian troops carrying automatic weapons. Oh sure, according to Russian propaganda Crimea is a tourist paradise... yea for Russian bureaucrats, Russian Putinistas and the Russian mafia to name but a few.
The population non-Russian and Russians alike are being regularly terrorized and innumerable human rights violations are taking place on an ongoing basis.
It is nothing short of tragic.