It'd only be a partial solution, but have you done any experimenting with using dice as counters? (Obviously you'd need to keep them separate from the ones you roll.) Hit points can be tracked on a D20 for low levels or %ile dice otherwise. Spell slots are one number per spell level. I've never tried this and don't know how well it would work, which is why I'm asking a question in a comment instead of writing an answer.

Yes, but it's very easy for someone to shake the table and knock a die over. We'd also need a clear way to indicate what counter-die would be for what spell level, or the paladin's Lay on Hands feature, and similar.

I played a game once (I forget what -- not an RPG but a dice game) where the dice were placed in foam "trays" that held each die. I guess it was a dice-drafting game. I started down that path but realized I needed more info.

About how many "things" does each player need to keep track of? Would half a dozen counters per player do the job, or is that way off? What about you as the GM -- how many things are you keeping track of in an encounter?

Off the top of my head: Each player needs to track 1.) HP 2.) spell slots 3.) inspiration. The Paladin needs to track Lay on Hands, Divine Sense, and Channel Divinity. The sorcerer needs to track Sorcerer Points. The Ranger has a magic item that she needs to track successes and failures on. I generally need to track HP for up to six creatures and initiative order, as well as legendary actions and resistances, plus lair actions.

Could you adapt something like this https://www.easypeasyandfun.com/printable-number-spinners-1-to-20/ or this https://www.craftnhome.com/number-spinners-for-maths.html instead of dice? For the former, the bottom circles would have the digits 0-9 on them and you'd label the top circles with whatever stat or number you're tracking. For the latter, you could put the label on the outside of the spinner. For HP, you'd need 2-3 per creature/character, and label them as "HP-1", "HP-10", and "HP-100" respectively. Any counted stat (like Lay on Hands) would work similarly. If you could make them a bit smaller than they look on that site, you could potentially stick them on a piece of paper to keep them all organized. After the sabbath is over, you and/or your players could update the character sheets as needed. It might take a bit of work to do/get used to but it could solve the issue of keeping tracking of numbers/points.