The issue that (IMO) was DECs downfall is exactly what brought them to the top in the first place. Price vs. reliability.

I started my career working on VAX machines. By the time Alphas came around I was working extensively on-site with customers.

Powerful PCs could be used as servers starting in the mid-90s. Alphas were rock solid and never failed. PCs had memory leaks and DOS errors that required periodic reboots of mission critical 24/7 servers. This terrified industrial customers at first, but it only took months to a couple of years to implement permanent software strategies to cover the hardware/software limitations of PCs.

By the mid 90s a somewhat stable PC server cost 10-20% what an Alpha server cost. Keep in mind that Moore's law was going VERY strong back then, so the new PC server was 4 times faster after two years than the old one.

Customers lived with the PC instability because the costs were so low and every couple of years they got new servers 4 times faster than the old ones. It was a no brainer business-wise.