Monopolies are wonderful if used responsibly. Having 1 standard way to do something across the board can solve entire universes of problems. Interstate highway system, electrical grid, internet, etc. all fall very cleanly into that bucket.

Splitting up a technology company like Amazon or Google would probably just make matters worse over the long haul. Instead of 1 obvious regulatory target you would wind up with several and this creates more shadowy areas for perverse incentives to grow like mold. Just look at how splitting up ATT has played out. It ultimately re-aggregated into more-or-less the same monster but with even more power and influence than in the 80s. If ATT would have been nationalized instead of split up, I'd have a hard time believing we wouldn't have better internet access on average today.