Yes, for data engineers ETL is necessary. Traditional ETL knowledge may be important as data engineers may need to collect data from many sources, transform structured and unstructured data into relevant information, clean up data, etc. Even it is better to upskill your career with ETL skills by learning some other data-cleaning tools and become a big data engineer. This field has a lot of demand in the current market. As observed by Forbes, a data engineer is one of the emerging jobs on LinkedIn. Upskill yourself with this big data masters program from Intellipaat.
Before that do check out how Sanjeev Singh upskilled his career from ETL developer to Data engineer -