Hello Sasha0015,
There is an awful lot of misinformation circulating regarding Macs and security these days. Apple used to have a reputation for good security due to the lack of any significant Mac malware. PC people always claimed that was because Apple was a "niche market" and the malware authors just didn't want to bother. It turns out that the PC users were absolutely correct on this one. Macs have had a couple of true malware incidents lately. Much more common, however, have been serious Apple software bugs or security failures. Apple neglected to verify web browser security certificates for years. Apple's app stores are currently suffering a significant security issue where apps you download for your iPhone or iPad come pre-installed with malware.
Here in Apple Support Communities, the most common thing people report is adware. What makes the issue worse is people relying on old habits and assumptions that are simply not valid. Then, they take it to the next level and tell people who are affected by adware that:
1) it is their own fault that they became infected,
2) Apple has effective malware protection and effective adware removal services, and
3) the most effective 3rd adware removal solutions are actually malicious.
None of that is true. Personally, I think bad advice like that is more malicious than the adware itself.
I used to have high confidence in Apple's security protections and in the advice provided here in the support forums, but not any more. I recently added a big disclaimer to my EtreCheck software requiring that users agree that I am not responsible for any bad advice they follow here on Apple Support Communities or other internet forums. EtreCheck also has some basic adware detection capabilities. But I rely on Apple's support documentation and that documentation is out-of-date and just plain bad. Consequently, EtreCheck can no longer detect recent adware. It will still list the adware as Launch Agents/Daemons, but it may not be identified as "adware". So I now automatically suggest people download and run MalwareBytes for Mac (https://www.malwarebytes.org/mac-download/) just to be safe, even if EtreCheck doesn't say anything about adware.
You will find many people here on Apple Support Communities trashing various anti-virus and anti-malware products. In many cases, they are correct. There is a lot of software ported from Windows that will bring your Mac to its knees while it scans your hard drive and your backups with every known Windows malware known - all of which is harmless to your Mac. These 3rd party anti-virus and anti-malware products are starting to improve. I have heard more encouraging reports about them lately. Some people have suggested that Sophos is more reliable and other people have reported that BitDefender prevented installation of some adware. Hopefully that trend will continue. But for now, the only anti-adware/anti-malware product I would recommend is MalwareBytes for Mac. It does not prevent installation of adware, but it makes removal quick and easy. Curiously, the most extreme incidents of trashing of 3rd anti-virus and anti-malware products is directed almost exclusively at MalwareBytes for Mac.
You specifically asked about Login Items in MalwareBytes. You should definitely use MalwareBytes to remove these items. What some people don't understand is that the list of "Login Items" in System Preferences is not a complete list. Any application can install its own login items using another method and they will not be listed in System Preferences. That is why you do not see those key loggers that MalwareBytes is reporting. It is because Apple doesn't show them to you. I recently added support in EtreCheck to report these new kinds of login items as well as other kinds of hidden tasks that are running the background. But unfortunately, I just don't have the resources to keep track of all the Mac adware and malware. It is reaching epidemic proportions. Sadly, and for reasons I do not understand, some people are doing everything in their power to make it worse.
