Re: 11 months to the day...
Most of our staff don't keep that much mail in their boxes, we discourage massive signature, and attachments are done by linking to the file instead of including it in the message itself. Plain text messages are also fairly common (Some people here joined the company before HTML mail was a thing, a few of the more senior staff learned to use computers during the bang-path days)
We've also offset the performance hit by removing the overhead that Windows was putting on the systems. Aside from the engineering staff (Who make up 60% of the company and were already running Linux), everyone's just been using browser-based applications hosted on local servers for their work, so after a little retraining, very few people have complained about the switch. At the very least, the switch was less painful than when we switched to Windows from Solaris back in the late 90s.
We don't really need much in the way of newer technologies, we manufacture, and support, machines for other manufacturers. We started building machinery for these new-fangled "Assembly Lines" that are all the rage and now make complex machinery that our customers use to build their products. So like our most popular product is a set of machines that cut, fold, and weld metal sheets into metallic cases for other products. We like to sum up our company as being a "Factory factory".