Well I'm GGL (which is presumably what "Gold Guests" means in the linked article) and have had disgustingly dirty seats occasionally. Last time I flew on BA was LHR->ZRH (a couple of weeks ago) the "middle seat" in CE (i.e. a table) had clearly not been wiped since the last flight as evidenced by the large coffee-coloured ring on the table. After pointing this out the crew wiped this with the hot towel, so no great issue, but the suggestion clean seats are reserved for golds is not the case. Personally I think having your seat area cleaned should not be a GGL/Prem exclusive thing - I think it should happen for all pax.