Is it true that "all prohibitions and forbidden desires in this world are permissible and lawful in the Afterlife," and that "homosexual love is forbidden in this world and the Afterlife"? And what is the motivation for abandoning prohibitions in this world?

The statement "a Muslim is asked to abstain from unlawful things because he will find them in Paradise" is not entirely accurate. This is because some things that are forbidden in this world, a Muslim will find in Paradise in a manner befitting it, such as wearing silk, drinking wine, and drinking from vessels of gold and silver. As stated in the Hadith: "(Whoever wears silk in this world will not wear it in the Hereafter, and whoever drinks wine in this world will not drink it in the Hereafter, and whoever drinks from vessels of silver and gold will not drink from them in the Hereafter)." Then he said: "(These are the garments of the people of Paradise, and the drink of the people of Paradise, and the vessels of the people of Paradise)." As for some other prohibitions, their perpetrators may be punished by being deprived of their counterparts in the Hereafter, such as singing and fornication. As for sodomy and lesbianism, the people of Paradise are purified from them.