What are you selling? If you aren't selling anything what is your ultimate goal - generating affiliate income? Receiving consulting inquiries? etc.
Whatever is important to you, measure it. You can probably use Google Analytics for that. It's free.
Once you start recording things that are important to you (use "events") then you can go into Google Analytics and find out what channel is working best for you here:
Concentrate your efforts on the channel that is giving you the best results. 80/20 rule here totally applies. Put minimum effort in on the other channels (just x-post your content, or interact if you genuinely enjoy it) and if things start to pick up there (review google analytics regularly, at least once a month, or more often if you find it inspiring, just try not to get caught up in measurement for its own sake), then focus more efforts on the best channels.
Here's my events filtered by source. Facebook was paid ads, but hasn't been working out so great in terms of ROI yet. Reddit and Indiehackers have been solid for me, so I'm going to continue spending time contributing content there. Content will get syndicated to my other social media outlets.
Author of the book Software Engineer's Guide To Freelance Consulting, teaching programmers to find freelance programming jobs