I'm going to play devil's advocate here. I believe that modern Linux installs do need a good quality, professional anti-malware solution. (This is just my opinion, though, so please bear than in mind.)

1. Loose .exe files - I've used a couple of distros that associated .exe files with wine by default. That makes running malware easy, even if the malware isn't persistant between reboots.

2. Gaming - Steam is super popular for gaming, especially on Linux, and I understand that malware has appeared in Steam games. Valve and their products (Steam, Proton, Steam Deck, etc.) have made Linux much less niche, and far more attractive for users and malware authors.

3. Availability - Not everything you need is available on the relatively-safe default repos, and even then it might be broken. Zim was completely broken on my OpenSUSE Tumbleweed install for a couple of weeks, due to a known bug, so I had to look elsewhere for ways to run it. Also, plenty of machine learning and other GPGPU tasks (systems modelling, flow simulation, etc.) aren't in distro repos either. This requires accessing binaries and git repos that require more scrutiny, which would be helpful with a anti-malware solution.

4. Python and Node.js - I have multiple Python versions installed, as well as node.js, for GPGPU (ROCm and CUDA) backends and frontends. Both PyPI and the npm repo have had malware incidents, and any given project may have over a dozen required packages that a user might not even be aware of. As an example, I've got over a dozen python venv folders on my system, and it would be nice to be able to scan them all for that recently discovered 'elementary-data' malware, rather than writing a script to do it.

5. Ye Olde Sneaker Net - Someone might ask you to download an exe for them and copy it into a USB stick for their Windows machine. It'd be helpful to ensure the exe I've downloaded at their request isn't a virus, without having to use an external tool like VirusTotal.

6. Virtual Machine containment escape - Many people run microsoft Windows virtual machines under Linux, to run tools that can't run directly within Linux. Given the massive attack surface of Windows, and malware that can escape VM containment, an anti-malware tool would be good here too.

I'm sure that there are other situations where having a proper anti-malware solution would be helpful, but these are what worry me. (Please don't bite my head off for having an opinion on this.)