What's the point in saving those wages if we are less on the pitch without him? And there's no evidence anyone would have paid a decent fee
There is no point in keeping him as he is here against his will, he is 33, and he will most probably leave next summer anyways, so whats the difference? Long term it would have been better to have sold him (and also save huuuge money on his wages), invested that money in new players and start the rebuild properly.
He will leave, it is inevitable and it makes like 0 difference if he left now or if he leaves next summer.