The numbers for total sims before culling kicks in haven't changed in a few years, so at least that number is still accurate, though you have it presented as a 'in total' number and it's actually a couple of numbers which combined add up to that. In my game I see culling start at around 630 sims total, because the cap for one category is just shy of that and it's where most sims in my game are categorized.
I can't say if the ghost timer for culling is still the same though, that's not a number I watch in the tuning files at all as I aggressively purge them early by releasing spirits.
