I'm in a similar situation; buying rentals but it feels so slow saving up for the next down payment. Just sitting on your hands waiting with nothing to do. So I end up reading online and watching videos seeing if there is SOMETHING else I can be doing to get the next property a little faster.
Maybe a flip, hard money, wholesaling, private lender, live-in, fix and refinance, but it just ends up not being the right thing for me, or no properties in the local market, or the risk doesn't seem worth it in the long run.
Along the way you see endless amounts of bad/the same content. Pretty much everything on Youtube is garbage, including the BiggerPockets stuff. Most podcasts are more entertainment than actual substance. Either that or this business just isn't that complicated and there isn't much else to learn unless you want to be a general contractor or tax professional.
Ultimately, if real estate is just a side thing and you're collecting rentals its a decent way to build wealth but its just going to be boring and that's the way it is. Maybe not as boring as index fund investing but still along the same vein.