I am only getting low download and upload speeds and the provider technician says Mac products have security that slows down the system. Is this true?

<< the provider technician says Mac products have security that slows down the system. Is this true? >>

for un-modifed macOS, that is not true.

For Macs with added:

third-party speeder-uppers, Cleaners, Optimizers, or Virus scanners. or a VPN that you installed yourself. -OR-

Third-party file Sync-ers such as DropBox, BackBlaze, OneDrive, or GoogleDrive can ruin performance, but are not inherently dangerous.

The only "security" I have found that plays havoc with Macs are useless third-party anti-virus and so-called "cleaning" apps. If you have those, yes, expect issues even beyond slow data transfers.

Client-side VPN's—the ones with adverts on the TV six times every hour—are also bottlenecks. VPNs are fine in a corporate setting but on the company's server, not end users' computers.

Macs protect themselves remarkably well and, cat-like clean themselves with elegant automated maintenance routines that you paid Apple to build into the system.

The quick test for added software causing problem is to restart into Safe mode, where most third-party software is not automatically added, and run the test again.

"works in Safe mode, fails in regular mode" implies "It's something you added"

For analysis of Wi-Fi issues causing the problem, post the snapshot available when you hold the Option key and click on the Wi-Fi Icon an the Menubar. transcribe or screenshot the report. looks like this older one:

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