Tawassul is not indicative of assuming distance from your Lord. It is to consider your own self as less deserving due to the sins you have committed.
What, other than tawassul, is supplicating to Allah by employing Allah’s names and attributes. Employing other noble and blessed things / deeds or people should also be seen in the similar light. Noble and blessed people remain noble and blessed even after death.
Prophet, blessing and peace upon him, told Umar ‘don’t forget me in your prayers’ before he left for ‘umrah. Umar said this was a great blessing of his life.
No one has said Tawassul is necessary. It is simply a way of Adab.