While the Germans were pioneers there was a long, long way to get to where they (or anybody else) needed to be.
There were earlier efforts.
Bruce, J. M.: 1957, British Aeroplanes 1914 - 1918. London, UK: Putnam. Second Impression 1969, pp 459-469 mentions a 'R.F.C. Experimental Works Radio-controlled Aircraft'. This apparently started with a direction to Professor A.M. Low <
Archibald Low - Wikipedia> to investigate the possibility of using a form of television to direct a radio-controlled bomb. Apparently tests were successful, but not a lot of details are available. They were not tried operationally.
On p 460 it says `It was the true ancestor of various devices which were used in the Second World War, preceding by a quarter of a century weapons which were claimed by their inventors to be the first of their type'.
The Wikipedia article says: `1917 Low and his team also invented the first electrically steered rocket (the world's first wireless, or wire-guided rocket), almost an exact counterpart of the one used by the Germans in 1942 against merchant shipping. Low's inventions during the war were to a large extent before their time and hence were under-appreciated by the Government of the day, although the Germans were well aware of how dangerous his inventions might be' and `During World War II the Germans also made good use of Low's 1918 rocket guidance system and used it as one of the foundations for their V projects'.
As people are no doubt aware of the difficulties in making such weapons work in WWII it is clear the WWI experiments needed a lot more work before anything would have become operational. Also I suspect Wiki is overstating the influence of the tests.
The British were ahead of German use of radio in WWI, in terms of fitting them to aircraft and introducing voice as well as Morse sets, so trying radio control is an obvious next step. The between the wars Queen Bee series radio control targets and ideas of using them or similar for strikes.