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The early PAL Sony Trinitrons were designed to avoid infringing the PAL patents. These were owned by Telefunken and in the UK were assigned to EMI. They were also used to prevent import of Japanese TVs to Europe.
The Sony design converted PAL to sort of NTSC (this is a very simplistic explanation) which was then demodulated as though it was NTSC. Hence a hue control was needed.
Simple PAL was different. You could demodulate PAL without using a delay line to average adjacent lines. Any phase errors then gave Hanover bars. When PAL was invented by Bruch at Telefunken a one-line delay was a difficult and expensive item. Hence the idea of a simple PAL decoder. Then Philips designed the original DL1 ultrasonic delay line which was cheap enough. AFAIK, no simple PAL sets were marketed in the UK.
Strictly speaking, in NTSC, if both the coding and decoding are done accurately then no hue control is needed. Even into the late 1960s and early 1970s the required accuracy and stability was not feasible.
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