It seems to be the norm these days with slots, longest I went was about 1000 Spins on piggy riches, I'm too stubborn to go. I recently waited 1600+ spins until a bonus on Ted megaways, that wasn't all in one go and after 700 on Griffin I gave up. There's no way I'm hitting rtp anytime soon, it'll take those million/billion spins to achieve.
Today on reactoonz (over only 360ish spins my rtp was 40%). Some slots are brutal and megaways can be, I like the mechanics of it, but lots of companies are jumping on the megaways band wagon, it seems to be where the shift change is happening. Just check out the bonanza thread to see how horrendous it gets.