Is it obligatory to act upon the fatwa that permits one whose urine drips for most of the prayers to forgo ghusl and wudu, and is his prayer valid in this state?

The mentioned fatwa has no basis. What comes close to it is the statement of the Malikis, who hold that whoever experiences urine discharge for half or more of the time is considered to have سلس (urinary incontinence), and according to them, he is not required to perform ablution for prayer. If the discharge is less than that, even if only once a day, he is not obliged to cleanse the area; rather, he only needs to perform ablution for prayer. As for the most preponderant fatwa, it is that if you cannot find enough time to pray with a valid purification, or if the time of cessation is not regular, then you are considered to have سلس (incontinence). It is sufficient for you to perform ablution after the prayer time begins, and you may pray as much as you wish until the time expires, and what exits from you will not harm you. However, if you know that the urine discharge will stop, even at the very end of the prayer time, then wait until it stops, perform ablution, and pray, even if you miss the congregational prayer. Praying with a valid purification takes precedence over praying in congregation.