I wear my Chucks all the time, and here's the thing: they only look old-fashioned if you feel uncomfortable in them yourself. Last year I got into kayaking and realized I'd been wasting way too much time before worrying about whether clothes "still work" or not. The truth is, good basics like Chucks just work. If yours still look good and are comfortable, wear them. Your friend might have a different style in mind right now, but that doesn't mean Chucks are suddenly out. They've been around for decades and they're not going anywhere.
What I've noticed: it really comes down to the rest of your outfit. Chucks in full 90s styling look different than Chucks with modern stuff. If you pair them with contemporary pieces, it doesn't look retro at all, just clean. And honestly, the sneaker industry has made such a big deal about new models that a lot of people don't even realize that Chucks are just... part of the picture. They barely change and that's exactly why they don't look old-fashioned, they're timeless.
Just wear your pairs. Less consumption is pretty nice anyway, and if you realize you really don't like them anymore, then get new ones. But that's a decision for you, not because your friend says they're retro.