RX Voltage Divider Doubt

Hi to all! My doubt is about connections between E220 modules and arduino (UNO, NANO) In E220-900T-22D datasheet I saw a image with connections between an generic microcontroller and E220 module. In the image all connections are direct without pullups nor voltage dividers. And in Mischianti connections diagram between E220 modules and arduino UNO, exist pullup and voltage divider on RX pin from the module. Well, in Mischianti text he recommend to use pullup in all connections to avoid freeze the module. And the recommendation is understandable. However, I could not understand the need for the voltage divider, since according to the datasheet it is clearly stating that both signals (TX/RX) are TTL, which is understood to be 5V tolerant. Is there any information I missed in the texts? Thanks Ivan Assaritti