Yup. It set back LGBT rights by decades; there’s a sizable chunk of an entire generation of the community just
gone, people who might today have become leaders, activists, and mentors for young LGBT people.
Reagan and the US government not only “turned their back” and failed to act for years, leading to conservative estimates of thousands of new infections that could’ve been prevented; they also also actively interfered: for example, Congress banned the use of federal funds for prevention campaigns that “promoted or encouraged, directly or indirectly, homosexual activities”. So a lot of the prevention campaigns became ineffective fear-based propaganda rather than what was needed: targeted education to vulnerable communities about safer sex and needle drug use practices.