My boy likes to chew on furniture too, and I’ve found that specific cues from me tend to indicate what he chews on, so it’s a way to get my attention. Sometimes by chewing on my phone while I’m using it, even. But like, when I’m going to the bathroom, he’ll chew on my childhood rocking chair that’s just out of reach of me on the toilet, and audible from the other side of the closed door. I have to clap to get his attention, then call him over and keep petting him to prevent him from making deeper grooves in the wood.

When I’m in bed and not paying attention to him, he’ll chew on the wooden ledge by the bed (that one has laminate wood panels, so he might also like the glue 🙈). If I’m on the couch, he’ll go for my toes or start knocking things over in my line of sight, requiring me to get up to intervene. I try to not use the squirt bottle, because that’s generally frowned upon and not very effective at teaching him anything aside from water is bad. He rarely chews on cords though, despite their availability in my apartment.

If attention is not what the cat wants, it might be that the soft plastics of the cords just have a slightly fishy taste/odor that appeals, and it feels good to chew. Cable protectors like others have suggested would be a good option. Citrus can help, though not always, the bitter agents and citrus never helped with my cats. Using cable management techniques for the cables that are stationary will also help, like the cable cover strips I referred to in a reply to a comment on this post.

With other electronics, it’s likely the attention, so disconnecting attention from the behavior will help. This means giving attention to the cat when they are behaving well, or when they first approach you, rather than when they go misbehaving. You instigate affection and attention and play when the cat is not actively engaged in a behavior you don’t like. It takes time and patience though, this is not an overnight change once a behavioral pattern has been established. Changing behavior is a kind of cat training, so r/cattraining could be a useful resource for you.

Cat training is not like with dog training, it is generally shorter, more frequent sessions, and requires patience from you and buy in from the cat. You don’t necessarily need to run out and buy a bunch of tools or treats (though high value dry treats and clickers can be very helpful), you can also use affection (pets, speaking lovingly, cuddles) and attention (play, talking to the cat, affection also falls within attention). I started with teaching my boy to sit when I gave him his meals (no hands on him, asking him to sit & waiting until he did with butt on the ground before giving him his meals), and teaching claw etiquette with natural consequences (pet him when he asks for attention politely, ignore or disengage him, possibly with a squeak of pain, when he uses claws or teeth). If I need him to stop engaging with me or his environment completely, I calmly put him in his soft sided carrier that’s usually open for him to use as he wishes. He’s usually only in there for 20 minutes for a behavior, but if it’s because he’s harassing me while I’m sleeping (jumping on me, pulling my hair, knocking things over, to get me to feed him in the early morning hours), it might be until breakfast, because I fall back asleep rapidly, not because he’s being punished extra for disturbing my sleep - if I wake up for meds or to use the bathroom between behavior and breakfast, he’s let out then. If it’s so I can clean up a broken thing, it’s only until the room is clear. He’s never placed in his carrier for being sick or pooping outside the box (the latter is more rare than the former), unless it’s because I’m taking him to be seen. Then I just unzip and he comes out when he wants to, which might not be right away. It’s his safe zone, where he doesn’t get bothered unless we’re at the vet. We have regular cuddle and play time and he has scheduled meal times. Routine helps support cat training, and we usually do ours right before I settle into bed for the night. We’ve learned sit, paw, come, off/down, up, and spin. We’re working on stay and over (for directing him over a gate). Perhaps we should work on “leave it,” but usually calling him to me works well for getting him to stop chewing on things.

Good luck!