This isn’t a foregone conclusion, just a number of things that are increasingly likely:
When a place becomes “cool” and “rich”, then they get job applicants that are all in on “get rich quick” and as they get to call shots they are ready to destroy the core value to pulp out some profit. Particularly older companies like Intel, IBM and Microsoft have had time for that mindset to promote into the positions.
Failing that, investors can rapidly corrupt existing leadership, particularly for “startups”. It might start sincere, but then when a relatively small bunch find themselves with a multi-billion dollar payday, pedal to the floor to ruin things.
Additionally, any major player not in a position to be a part of the fun will make their knock-offs and market or monopoly their way to displace. Oh look, Microsoft Teams…
There’s a moderately successful, but also reasonably modest company that went about 50 years without getting “enshitified”. The founder was passionate about it, kept the company private, and held in until his 80s when he finally decided he really couldn’t do it anymore. Then they went public and immediately the layoffs, price hikes, and cloudification commenced, as the flood gate of enshitification opened on his retirement.