I can open the following link in Chrome on my PC, but my phone browser, which is also the latest version of Chrome, doesn't open it: ftp://tchdata.eili.ir (can only be accessed from Iran)
How can I open such links on my phone (Huawei P smart, if relevant)?
Chrome initially planned to depreciate support for FTP from version 81 but paused it because of COVID-19 (to help hospital staff access FTP resources) . In version 86 (currently latest on Play Store) , support to FTP has been depreciated for 1% users and by Chrome 87, it will be depreciated by 50% (Source).
So if you are lucky (not in the 1%), enable FTP flag by pasting chrome://flags/#enable-ftp in the address bar and launching Chrome again by pressing the prompt at bottom right.
Verified with this FTP site ftp://ftp.heanet.ie/ since link in OP can be accessed only from Iran.
If you can't access using browser, see this for other methods
How to connect an Android device to an FTP server?
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