Have you actually tried talking to a real Spanish speaker since you started, even for just a few minutes?
Here's the thing - you're right to be skeptical, but you're probably getting more out of it than you think. AI conversations do have limits. They're patient in ways real people aren't, they don't have accents that vary wildly, they won't interrupt you or jump topics randomly, and they'll sit through your slow thinking without the awkward silence that actually happens in real life. Those gaps matter because real conversation has rhythm and pressure that forces you to think faster.
That said, three months of consistent practice isn't wasted. You're building vocabulary retention, muscle memory for grammar patterns, and confidence saying things out loud (assuming you're speaking, not just typing). Those fundamentals transfer. The gap between practicing with an AI and talking to an actual person is real, but it's smaller than the gap between studying grammar rules on an app and doing either one. What you're missing is the unpredictability - someone who doesn't correct you when you're close enough, someone who uses slang you've never seen, someone who gets frustrated if you're too slow.
My suggestion: keep the AI sessions going, but at three months in you should find even one real conversation partner - a language exchange partner online, someone at a local Spanish meetup, doesn't matter. Do like one 15-minute conversation a month with a real person and see how it actually feels. That'll tell you what gaps exist and whether the AI practice is setting you up well or leaving you blindsided.