Why we couldn't transmit Electricity wirelessly even after so many proposals available proposed by Tesla ?
Tesla tried to generate more interest in Wardenclyffe by revealing its ability to transmit wireless electricity, but Morgan was not interested, and the 1903 "rich man's panic" on Wall Street dried up any further investment. By July 1904, Morgan (and the other investors) finally decided they would not provide any additional financing. In May 1905, Tesla's patents on alternating current motors and other methods of power transmission expired, halting royalty payments and causing a severe reduction of funding to the Wardenclyffe Tower. In an attempt to find alternative funding Tesla advertised the services of the Wardenclyffe facility but he was met with little success. By this time Tesla had also designed the Tesla turbine at Wardenclyffe and produced Tesla coils for sale to various businesses. Source
In 1891 and 1892, Tesla demonstrated the oscillatory transformer that bears his name in lectures delivered before meetings of the American Institute of Electrical Engineers (AIEE) in New York City" and the Institute of Electrical Engineers (IEE) in London, and in a later presentation titled "On Light and Other High Frequency Phenomena" (Philadelphia/St. Louis; Franklin Institute in 1893), where he put forward his ideas on the wireless transmission of electrical energy.
The Tesla coil wireless transmitter