High spec server running slower than low spec one?

We use numerous server companies for different reasons at work. We needed a bigger server and have treated ourselves to a

New server

   VMWare CPUs 4
   Cores per socket 1
   Bus type lsi logical parallel
   16MB
   Ubuntu 20
   MySQL 5.7

Old Server

   CPUs 2
   Cores per socket 1
   Bus type lsi logical parallel
   8MB
   MySQL 5.5

Old server performs better than the new one we've been upgraded to... The same MySQL queries take longer (and state as much) on the new powerful server. Loading any web page hosted from this server seems to take a while whereas this wasn't the case before.

When I use htop to compare servers, the old one which runs faster is maxed out in terms of CPU and memory. The new one is barely breaking a sweat.

I have noticed that when I ssh into the new server it frequently staggers and seeing the input on my terminal of what I'm typing is delayed.

I've asked the company to investigate but they ask silly questions about IPs and talk about temporary outages on a specific morning (nothing temporary about this issue).

I've exhausted my knowledge of how to extract metrics, numbers, etc that shows what's behind this issue.

Possible reasons

*) Either the host node is overloaded, can degrade the performance

*) Any bandwidth restrictions could be in place

*) Check the firewall rules on new & old server