You run a risk from co-mingling different activities. Your other activities pose a risk to your Bitcoin, and your Bitcoin node poses a theoretical risk to those other activities. The less activities on a single computer, the less chance that one of those activities will result in a security breach.
For example, if you are browsing reddit on that computer and click a link which exploits your browser and gives a third-party access to your computer, they will also have access to your Bitcoin wallet. That's not possible if the only thing on that computer is the Bitcoin wallet and you never use it for web browsing.
The risk goes the other way too. If there is a security vulnerability in Bitcoin core that enables access to your machine, your use of Bitcoin could mean somebody gets access to your browser history. This has never happened before, I would say it's much much less likely, especially if you have not setup port forwarding and therefore are only connected to a handful of nodes regularly, but it's not impossible.
Ultimately you will have to decide how much security you want and what cost that security is worth. If you are just playing around with small amounts of funds, you probably don't need to worry. But as you increase the amount of funds you are storing, you will probably want more security and be willing to do more to have that security. Having more Bitcoin in your node doesn't do you any good (unless you have it locked up in a lightning liquidity channel or are regularly spending much of that balance). Instead, mulit-sig, cold storage, and other solutions probably make more sense.
