Why did some organ musicians object to equal temperament?

Some organ musicians objected to equal temperament because it requires the total loss of perfectly tuned intervals, with the exception of the octave. While equal temperament allows for playing in all keys, it achieves this by slightly mistuning intervals across the entire chromatic scale.12

For the organ, which possesses a pure and sustained tone, these intonational defects are often considered to outweigh the system's benefits. In contrast to instruments like the piano or harpsichord—whose characteristic sounds are already rich in dissonant components—the organ's clarity makes the compromises of equal temperament more noticeable and less desirable to many musicians. Due to these concerns, some organists, such as Samuel Sebastian Wesley in England, continued to oppose the adoption of equal temperament as late as the mid-19th century.1