Get users by role with taxonomy sql

user-by-taxrole.sql

SELECT DISTINCT
    u.ID,
    u.user_login,
    u.user_nicename,
    u.user_email,
    u.display_name,
    m2.meta_value as role,
    GROUP_CONCAT(DISTINCT m.meta_value) AS terms
FROM wp_users as u
LEFT JOIN wp_usermeta AS m  
    ON u.ID = m.user_id
    AND m.meta_key = "um-taxonomy-category"
JOIN wp_usermeta AS m2
    ON u.ID = m2.user_id
    AND m2.meta_key = 'wp_capabilities'
    AND m2.meta_value REGEXP 'expert|author|editor|administrator'

GROUP BY u.ID
ORDER BY m.meta_key

To exclude users who do no have any taxonomy assigned to them, change the LEFT JOIN on line 10 to a normal JOIN

To filter users by a specific term or set of terms, add the follwing immediately below line #12:

AND m.meta_value IN (1, 2, 3)

1, 2, 3 being the term_id's for the terms to filter by.