I play on an XBox Series X and I've built up Spectacle Island pretty big, but I've started noticing that the game only crashes when I'm at Spectacle Island now. I've got about 40 settlers, but all of the Residential plots are multi-person homes to cut down on the buildings. I have one of each available Agriculture plots, Mechanical plots, Municipal plots, Commercial plots, Recreational plots and so far only one defense plot. I'm using turrets on stacked foundation stones spread around the island for offensive defense. I do have foundation stones down across all of the island in 3 levels. So that might be hurting it a bit too. I'm thinking about scrapping the whole settlement & going with less build up using foundation stones only for pathways instead.