Imagine Shen Yuan as SQQ mourning the loss of modern amenities like toothpaste the whole time but he can't complain to anyone about it except the system which doesn't really care.
Even after knowing about SQH he just presumed that SQH also was suffering the same fate only SQH just had them the whole time. Could be via the System in exchange for B points or he just wrote them in his personal notes while world building and realised that they existed at some point in time after transmigration and got them because he be An Ding or something like that.
Like SQQ just misses toothpaste a lot one day and complains to SQH only for SQH to carelessly be surprised, "What do you mean you miss toothpaste?" Realisation hits SQH that the stuff was in his personal notes so SQQ as he has previously presumed didn't know about all that. SqH is pretty dead if SQQ knows about it but the pause in conversation while SQH realised his mistake was long enough for SQQ to come to his own conclusions and yeah, SQH is pretty dead (don't tell MBJ)