@hungrybirder I agree this is a good group of people with good knowledge and good intentions - trying to help each other get better.
If -2.3 is your recent T-Score for your hip then you are not too bad there. Hopefully if you look at your T-Scores over time you can see a reasonable consistency to them. If they jump up and down much without a strong intervention of some kind the scores are probably suspect. For instance my scans show a pretty strong downward trend. Not good but at least I can see that scores are likely reasonably accurate and that helps me decide how to act.
If you could figure out what readings seem accurate for your spine that would help decide your course of action.

As to your original questions I think you can potentially go back to Fosamax or Reclast but it depends. How many years on each? How long ago? Any bad side effects? Do you have T-Score changes for the drugs? Those drugs do slowly leave your bones but they stay there for years. You can I believe use the ctx bone marker to judge how suppressed your bone turnover is. You use these anti-resorptives to suppress bone turnover but you have to weigh that against suppressing bone cleanup so much and so long that your bones have less and less quality.

Like a number of others on this site I like the idea of the anabolic meds to build bone being given priority over the anti-resorptives to prevent bone turnover. Prolia I think, again like some others on this site, is way more dangerous than the other meds. Maybe it's reasonable in some situations but the way it's now promoted seems just nuts to me.
Don't feel like you have to make an immediate decision. Bones are slow. Think it through carefully and take your best shot.

As for me I've got my 9th Evenity shot tomorrow (my first osteo med) with no significant side effects so far. I'm also doing 3 very different types of workouts, each one twice a week with one being a modified version of the LIFTMOR protocol. I also walk a couple of miles most mornings usually with a weighted vest. I also exercise and walk in ways that are mostly fun for me. It's not drudgery or something I hate to do. For instance one of my workouts is the Beat Saber vr game. It's the most fun ever and what a workout if you so choose to go at it as I do.
I do what I can to eat in a way I think makes sense but that's very complicated by food sensitivities so it would not make sense to others. I take additional calcium because my diet is way too low in calcium. I take some other supplements too but that's limited again by food sensitivities so the choices would perhaps seem odd to others.
So I do the med, I do the weights and other exercises and I do whatever else I can to keep my self healthy and feeling good in a general sense. I would love to improve enough bone wise to feel like it's safe to play pickleball and badminton again.