Why you need to start upgrading from Drupal 7 now

There's only one year before support for Drupal 7 support ends, but there are still more than 337,000 Drupal 7 websites, according to https://www.drupal.org/project/usage/drupal.

Even though there's a year left, if you've got a Drupal 7 website, you need to start upgrading now!

Unlike upgrading from Drupal 8 to 9 or 9 to 10, upgrading from Drupal 7 requires major changes to your code for it to be compatible. This will take time to do and test.

Most websites have some or many custom modules and at least one custom theme that must be upgraded.

Most use a large number of community-contributed modules.

Many of these are abandoned or minimally maintained as their maintainers have focused on newer Drupal versions or a module has been marked as unsupported in favour of another.

If they do have supported versions, it is likely that they haven't had a release for some time. If that's the case, they're essentially unsupported.

Because of this, there may not be the same modules available with the same functionality for Drupal 10.

Depending on the available modules, your functionality may need to change, or the old functionality will need to be written within a new custom module.

Here's the thing

Depending on the complexity, it will take a number of months to complete an upgrade.

Rather than wait until 2025, you want to do the work now whilst Drupal 7 is still supported rather than waiting and being vulnerable to security exploits if running an outdated and unsupported version.