Why is loading no longer the main concern?
Back in the 1970’s and 1980’s, acoustic guitars did not have the sophisticated pick-ups and built-in pre-amps that are standard today. Electric basses now incorporate high-output pick-ups or have active electronics built in. Keyboards inherently have high output levels. These high output levels are so powerful; loading is no longer the concern. This ‘fix’ has in fact caused a new problem; input distortion or saturation.