Not an expert in the area, but being passingly familiar with other major advancements and the timelines it's taken them to move from discovery to day to day use.
Let's say we got a massive wave of independent replication of superconductivity tomorrow - at least enough to convince Big Money to move in, and it all ends up being For Real.
The next steps are figuring out the other properties of the material, with a big one being 'how ductile is it', how to produce it in large enough quantities to be useful, if the underlying mechanisms here can be applied to other compositions that allow us to make RTAPS with better properties, etc.
Depending on those results determines the range of applications it is suitable for out of the box, how much we can make at what cost, etc. We've got minimal details to go on there. It's a ceramic, so it's probably not super ductile, but we have some experience in making those be useful via making them into a tape, a la YBCO. Can we do the same thing here? Who knows!
There's a timeline where all of these questions end up favorable and 10 years from now we see RTAPS in all sorts of day to day applications - we might find out that with one small trick we end up with big pure samples of LK99 with easy production methods. There's a world where all these answers aren't favorable, and it takes 10 years for it to show up in specialized applications (which are still huge for science and humanity!), and trickles bit by bit to more use cases over another few decades.
I would guess that a decade-ish is really the earliest window for significant impact to humanity - we're probably going to spend the next year at minimum figuring out what all the deal is with LK99, and then it'll take a few years to even really start making cool experimental stuff in labs, and then you have to actually productize things using it, etc.