Philosophy will cease to be relevant when thinking ceases to be relevant. I would cast suspicion on the intentions of anyone who wants people to stop reasoning and questioning.
In the past, it might have been suggested that philosophy should be made available to the consuming masses because they would be somehow liberated through it and made masters of their own destiny or whatever. Yet as time goes by, I’m less confident that the masses even want that purported liberation, at least not if it threatens consumption. Remember how throughout the 20th century, the average man rolled his eyes at those socialist-party members who kept banging on about the need to rise up against the system? Well, those encouraging thinking and reflection can expect the exact same response.