Pretty much all (<95%) automotive leather is PU coated and sealed. All these proprietary preparations do nothing to feed or nourish these leathers and can if over applied leave a sticky film that attracts grit, accelerating damage.
Of utmost importance is to keep seats free from dried on dirt and grit, which if left in creases, will grind away at the coating causing cracks and the damage is done.
I routinely (weekly) wipe down my seats and seat backs with a damp microfibre after carefully vacuuming with a soft brush attachment. I do use the executive leather care kit supplied by Lexus, perhaps 2-3 times a year. This deep cleans the surface and reapplies the protectant applied at the factory.
I did have a naked nappa leather retrim in my Mercedes, looked incredible, was beautifully soft and comfortable leather (actually not that dissimilar in feel to the leather in my RC!) but my word, was it hard work to keep clean. Being naked it needed careful cleaning and nourishing at least once a fortnight. Dye transfer was always a problem. My local dealership had very strict instructions on keeping the seats covered during service. All the techs knew not to touch the leather with greasy hands! Never again...