Getting back into poker - how much has course content changed in recent years?

I recently got the poker itch again after being away from the game for 3ish years. So far been mostly easing back into it with very casual 2nl and 5nl rush n cash on GG and I want to try to take it a bit more seriously again, probably depositing a solid bankroll for 5nl and going from there.

I've been watching some content on twitch/youtube to get some more feel for the current theory and it does feel slightly different than what I remember it to be which is partly why I'm making this thread. Most notably I remember that betting small on the flop IP in single raised pots on favourable boards was just a slam-dunk obvious continuation, but from what I've been seeing there is (slightly?) less of that nowadays with IP choosing to check back more often than I remember it. My empirical observations could very well be wrong but noticing the trend caused me to create this thread.

Back in 2021 when I last played I did purchase some courses (RIOs FTGU, RYEs Online Cash Apprentice) and they did well for me back then. My question is, how well do those courses stand in the current online poker game? I figure FTGU stands the test of time quite well as it's a very generalised course designed to teach the player the basics and what to think about during a hand rather than just tell them what action to take when they see certain textures. Online Cash Apprentice does feel slightly less evergreen than FTGU as it gives the player a more ABC strategy to directly apply rather than teaching a framework.

I also wanted to check out if there are any differences in preflop ranges nowadays as I've always used the RYE ones that came with the course. I figured out GTO Wizard had some for free which is what I compared the RYE ranges to and they appear to be noticeably different, further leading me to believe they might be outdated.

I guess I could summarise my questions as:
a) Are there any worthwhile courses out currently which give an up to date approach to poker strategy (for microstakes) other than FTGU?
b) Are GTO Wizard ranges the standard (or close enough to it) for preflop play (for microstakes), or are there other "better"/more practical ranges out there?