The advantage of using MAX17221/3/5 with GPIO to drive EN is that you don't have to worry about sizing the GPIO to fight against the internal 100kohm , and the excess leakage current associated with the internal pull-up.
MAX17220
Production
The MAX17220–MAX17225 is a family of ultra-low quiescent current boost (step-up) DC-DC converters with a 225mA/0.5A/1A peak inductor current limit and...
Datasheet
MAX17220 on Analog.com
MAX17222
Production
The MAX17220–MAX17225 is a family of ultra-low quiescent current boost (step-up) DC-DC converters with a 225mA/0.5A/1A peak inductor current limit and...
Datasheet
MAX17222 on Analog.com