Over the years, communities have suffered not because of external threats but internal ones. Frankly our woes have less to do with our Q&A sites losing relevance than forgetting that the community built this network and focusing on things other than that to the detriment of the Stack Exchange Q&A.
Historically downsizings have been due to SE's 'other' projects, careers and teams getting pushed hard, with a heavy marketing and hiring focus on that. Last year, SO Inc. doubled their sales staff - and that team apparently took the worst hit. We also generally seem to lose some of our most experienced and beloved CMs and staff as part of the downsizing (not that we value any person who works with us less!) - which indicates the people making this decisions seem unaware of the impact people have had.
Frankly, the company has to do better by us, and expecting the community to pick up where they have consistently dropped the ball is unfair.
If I felt the company actually had our interests at heart - I would say being an advocate for the company's paid products such as Teams, either as a decision maker, or as a individual contributor would be a start.
The platform ... doesn't matter. The communities and people do. That there's anything left is a testament to the very strong foundation we have. That said, the strongest foundations can weather away.
We keep the network strong by fighting the good fight. We share our knowledge, we help new users find their feet. We stay mindful of the impact we have on those we touch. AI could give you answers fast, but sometimes, you need answers from someone who actually understands the problem. Frankly, we'll survive AI. Surviving management decisions such as "We'll downsize the community team, it'll be fine" or antagonizing the community that contributes for short term goals - I'm less sure about. If Stack Overflow falls, something else can fill the void for you. Perhaps Codidact, or something completely different. The company and platform needs the people, not the other way around.