Does Different MTU Communicate

A dicey sitution occurs when MTU on different interfaces come in picture. Every is having a thought process that the lowest MTU on interface will negociate each other but in fact, it only works in case of path mtu is enabled. Assume a scenario where a R1 router is connected with R2 router. R1 interface is having MTU of 1500 bytes and latter is having MTU of 1600 bytes. If R1 sends a packets of 1501 bytes to R2 without DF bit set, R1 will fragment the packet and forwards it to R2 reassembles the packet and will forward a single packet of 1501 bytes to R1. R1 interface will drop the packet because the interface MTU is set to 1500 bytes and communiaction will never occur in case of packet size more than 1500 bytes.