Well... I've always believed that a good go to market should be extremely multi channel with paid being gravy anyway. I think DigitalOcean was successful because we did a combination of: Actually useful content marketing + being where your customer actually is (so attend&host event/conferences etc) + genuine community outreach and interest in what your customer base is all about (I spent time every day during DO on HN making sure if anyone had a problem it was solved) + for devtools (at least back in my day) I think supporting OSS meaningfully was also incredibly important. To a degree in DevTools, DevRel can basically be the same as paid influencers, I had Mikeal Rogers (rest in peace) working for me and his mission was "Do whatever you want as long as it's net positive to the nodejs community, have fun!" so I guess "paying influencers" can mean few diff things. With youtube a lot of people use sponsor blockers now too so paying someone to shill your shit in the middle of their video is probably not as effective as it once was, tho I doubt the sponsor blocks are as widespread as ad blockers.
If you're just getting started I think the best thing you can do by a mile is just attend conferences/events where your ICP is and try to bootstrap PLG with it.
This question is asked often, and the answer is always that it depends on who your audience is. Channels that work for one person might fail for you, and vice versa. Every product solves a different problem, which means different people who seek out information from different places.
Step 1 is to understand who those people are for your product, and figure out which information sources they trust. As implied above, almost nobody trusts online ads.