Most accessible would be imo are TL, IPT, PHD, HDT. You can join all these trackers right now with a donation or buying a seedbox for one month to get an invite.
TL/IPT are general trackers, I would prefer TL over IPT personally, they have a good amount of HQ encodes, remuxes, WEB-DLs....but I also find them good for re-encodes / x265 encodes. Particularly when you don't need the best quality of some TV series and want to save space. Groups like QxR (ImE, Silence, Panda, Tigole, etc), TAoE, Vyndros, EDGE2020, YAWNiX, etc are pretty good for them here. TL also opens often for free signups, they probably will like 2 more times this year, usually around holidays.
PHD/HDT I would consider more "HQ/HD trackers" they have restrictions not allowing some uploads, i.e trackers like these will usually ban those x265 groups I mentioned before deeming too low quality. But they have lots of remuxes, web-dls, and HQ encodes. PHD in particular usually is very fast with pre-times on latest p2p releases from groups like NTb, TEPES, FLUX, LAZY, KiNGS, etc as they upload. They also have a lot of remuxes from EPSiLON and their current remux group TRiTON.
I can't comment much on IPT or HDT, but know they are similar to TL and PHD respectively.
The downside of these trackers, generally, they're dead ends to getting into other trackers. They don't have invite forums. PHD has a way to access the AvistaZ sister sites....trackers to get into other trackers becomes a whole different can of worms.
Personally, I've moved onto different trackers for the most part...but do still occasionally use PHD and TL. Sometimes PHD is faster to upload things. Sometimes, just by the sheer size, TL has more stuff. I would have said look into /r/opensignups for when trackers open up...but on the fediverse I don't know a comparable place.
Hopefully this helps!