Focusing only on the tools
Sometimes in IT we can loose sight of the overall purpose behind IT and the service we provide to a business. We'll often focus only on the tools we use whilst loosing focus on their overall purpose and effect that the tool should have on the business (the output).
For example, if this were /r/carpentry, we'd see some people who are entirely focused on saws, blades, and what kind of planer is best, with little care to what they're building or what the tool is even used for or what the customer is asking for. Or they're trying to plan their career around one type of bandsaw, one brand of tool, or building one specific type of bookcase like that's all they're ever going to do. While tools are certainly important, the end-result is the finished product, not *the tool itself*. Do you only ever want to operate 1 or 2 tools in your entire career?
In the case of IT, the finished product is rarely "the server" (unless you're a tech company), it's the information, apps, data, and services the server provides the business. Servers (or other technologies) simply help provide that finished result or product.
Typically when we see the whole 'IT is dying' or 'Sysadmin is in decline' post, it's someone who's focused on a specific set of tools or ways of doing things, whilst ignoring the point of the tool and the output it provides. This is where we run into the situation of *'If the only tool you have is a hammer, everything looks like a nail'*. Tools come and go, but the need for the finished products does not. Building methods come and go as well.
For example, a CFO might need a report about what widget is the most profitable in each continent. 40 years ago that was probably an accountant tracking it all on a paper ledger. 20 years ago that might be a business analyst using a spreadsheet or access. Today, that might be a Power BI widget in Azure, or a Jasper report from a CentOS VM in Amazon. In 20 years its probably going to be a totally different tool.
We build houses very differently today than we did 100 years ago, but the need for houses is still there and as strong as ever. Photographers generally don't spend most of their days in darkrooms anymore, but that doesn't mean 'photography is in decline'. One of the reasons Kodak went bust is a failure to adapt to the changing marketplace and digital. But photography itself is as popular as ever. What is ultimately important is the apps, data, information, and communication tools we provide to the business. Some specific tools and technologies are in decline, others are growing. Some require fewer sysadmins to manage, other tools need sysadmins with new skills.
Remember, the tool itself is rarely a value-add to the end customer in a given business. When's the last time you bought a car and asked whether the metal stamping machine used on the rear fender was a Akyapak or a Dimeco?
We as sysadmins and IT professionals need to remember that the tools might change, but that's not typically what matters to the business at the end of the day. Especially at the junior level, try not to hyper-focus on a specific tool or technology, rather how they're used to accomplish a goal or solve a problem. As you grow in your role, you'll deal less and less in specific tools and more into the results and how they affect the business.