That depends on a number of things actually.

Personally I have 4 quick and 240k banked after about 16 month of play, so that sounds about right to me. But it's not linear nor consistent.

For one thing, it really builds up once you are capped, since there aren't many other place that you c*e coins barring donating to group. For player who are still growing, coins are a much more precious commodity. If a player do not level freeze/slow level, they are usually a deficit until late 70s, so it could easily be months before you get your first one.

Second, level freezing. One of the biggest source of coin, accounting to maybe 30% of your overall potential income is fox. Well, guess what, level freezer stay away from that like the plague. And as such, along with other potential coin reward going unclaimed, such as some of the daily mission reward, their coin income would be significantly lower. Not to mention I believe some coin rewards, such as S convoy, are tied to level and thus even less coins. And if you have some kind of fixed cost, such as group donation, then the disparity is even bigger. Overall, a level freezer might have only half or less of the disposable coin income of someone who don't freeze, so the rate would vary.

Third, donation habits. Group donation can be expensive. Now, I'm not exactly an advocate of max donating everyday. It's not particularly efficient. However, I do consider donating enough so you can spin the wheel the maximal number of times could potentially be a good idea in the long run. Specifically, in the long run, 8 gate will reach horrible return rate as you progress pass lv 9 or even cap completely. At that point, spinning wheel might be more profitable for the bit of coupon etc. Given that, since unused spins are effectively wasted and lost forever, some player might decide to start doing the donation for spins early, before their 8 gate starts to saturate since 8 gate aren't going anywhere. This would therefore significantly delay 8 gate progression.

And while this isn't quite relevant YET, there was the golden age of group activity rewards. That were some nice extra coins. Players who have started recently after its removal might end up in worse shape. Just want to put it out there even thou it's not relevant yet. Granted, I'm not completely sure if 4.0 really does have a lower coin income per day on average since there were a number of adjustments. But it doesn't hurt to put this out there.

In any case, my point is that while eventually the loss of 20k pt becomes not a big deal, for many players quick rune are still a precious commodity. Not everyone have hundreds of thousands of points stockpiled (where is the bloody red chakra exchange, I'd like one red fire and one red lightning tyvm).