Spending on backlinks when traffic's already down feels risky — I’ve been in that spot too. But from what I’ve seen, without any link-building or engagement signals, Google just treats the site like thin content, especially now with all the AI detection stuff.
If you're not ready to go all in with a link budget, maybe start small — a few niche edits or even some solid internal linking can sometimes move the needle. Or repurpose some content to make it feel more personal and helpful. That alone can make a difference.
Also, maybe pick the best-performing site out of the bunch and focus on fixing just that one first. Less overwhelming, and you’ll get better insight into what’s working and what’s not.
Hope it turns around for you — been there, and I know it sucks.