Overland Expo West 2019 will mark my 7th expo (four easts and 3rd west). It will also be my 6th as an instructor.
As echoed by previous statements, there is a LOT going on at expo. There's a social layer (the people), a trade show layer (the vendors), and the educational layer (workshops). No single human can do all of one area let alone the whole show. What you'll need to do is decide what you want out of expo. There is no one right way.
I can say the classes are well worth it. Lots of great information. However, as some as mentioned, there's some misinformation in some of them too, however In my opinion that's gotten less so over the years. The bar has slowly gotten higher each year. I'd say do you homework and do a quick google each of an instructor if you're interested in their class.
That said, there's also a lot to get out of it from the trade show aspect. There will be tons of vendors and if you manage to visit them all you'll probably have blisters by the end of the event (bring good footwear, extra socks, and lots of foot powder). Don't let the commercialism get you down. Yes there will be tons of people selling you their wares, but there will also be a lot of great people with great companies making great products who clawed their way passed the big corporations to carve out their little corner of the market. Those are usually the best ones to talk to.
Socially, well, after hours at expo is something that can only be experienced. No story, photo, or video will accurately capture happy hour, post-happy-hour, and the post-post-happy-hour life at expo. Not to mention all the fireside chats in the camping area.