Steps to reproduce the issue

• setup plain joomla4 instance at php 8.0 or 7.3 or 7.4 with mysql 5.7
• keep standard setup values for uploads
• set server memory_limit to -1 (=no limit)
• upload an image via Menu -> Content -> Media

Expected result

• image uploaded

Actual result

• error message ""This file is too large to upload."

System information (as much as possible)

• shared webspace on Ionos with PHP 8.0.9 mysql 5.7.33
• standard memory set up on serverside is memory_limit=-1 (nolimit)
• php settings from joomla4-system information
  Upload Max Filesize | 64M
  Post Max Filesize | 64 M
  Memory Limit | -1

Additional comments

• tested on IONOS - Unlimited Plus - Shared Webhosting (everything is working fine on a joomla 3.10 instance on same webspace)
• tested with different image file types and sizes (from 1KB to 8MB)
• after creating a php.ini or .user.ini with "memory_limit="1024M" it worked well - i also tested lower limits like 32MB, 138MB etc.
• reference discussion: https://forum.joomla.org/viewtopic.php?f=811&t=987786&p=3636942#p3636942