Assuming every one of those overnight stays means two days spent in Berlin, and if they are spread out over the year, that's 175 thousand tourists at any given

Assuming every one of those overnight stays means two days spent in Berlin, and if they are spread out over the year, that's 175 thousand tourists at any given time, about 5% of the population. Of course they'll congregate in certain locations and certain times of year, but you're overstating the case. Instead of shaking your fist at airplanes flying overhead, maybe try increasing the hotel tax and cracking down on AirBnBs. Of course, you'll probably encounter opposition to this because some locals are making a great deal of profit.