So recently I completed side gig from random freelancing site where I had to shadow troubleshoot performance problems over teams call with random Indian guy on his client's AWS account. Long story short you can autoscale new instances all you want but it's not gonna help if your FIFO sqs has only one message group ID. This architecture is running an online game, which is basically limited to processing ONE event at the same time for ALL players xD
What's even better, basing on naming convention I realized it's a company that I interviewed for like 4 months ago and they told me "we need someone with more experience". Well good luck, thanks for quick cash