This error is encountered when data in the NextCloud database is not stored in the expected for:

php occ -V
An unhandled exception has been thrown:
OCP\Exceptions\AppConfigTypeConflictException: Config value bruteforcesettings/enabled is stored as boolean but was requested as string in /var/www/html/lib/private/AppConfig.php:537
Stack trace:
#0 /var/www/html/lib/private/AppConfig.php(385): OC\AppConfig->getTypedValue()
#1 /var/www/html/lib/private/AppConfig.php(1889): OC\AppConfig->getValueString()
#2 [internal function]: OC\AppConfig->OC\{closure}()
#3 /var/www/html/lib/private/AppConfig.php(1887): array_filter()
#4 /var/www/html/lib/private/Memcache/Factory.php(122): OC\AppConfig->getAppInstalledVersions()
#5 /var/www/html/lib/private/Memcache/Factory.php(163): OC\Memcache\Factory->getGlobalPrefix()
#6 /var/www/html/lib/private/Server.php(936): OC\Memcache\Factory->createLocking()
#7 /var/www/html/lib/private/AppFramework/Utility/SimpleContainer.php(169): OC\Server->OC\{closure}()
#8 /var/www/html/3rdparty/pimple/pimple/src/Pimple/Container.php(122): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#9 /var/www/html/lib/private/AppFramework/Utility/SimpleContainer.php(136): Pimple\Container->offsetGet()
#10 /var/www/html/lib/private/ServerContainer.php(154): OC\AppFramework\Utility\SimpleContainer->query()
#11 /var/www/html/lib/private/AppFramework/Utility/SimpleContainer.php(45): OC\ServerContainer->query()
#12 /var/www/html/lib/private/Files/View.php(77): OC\AppFramework\Utility\SimpleContainer->get()
#13 /var/www/html/lib/private/Server.php(423): OC\Files\View->__construct()
#14 /var/www/html/lib/private/AppFramework/Utility/SimpleContainer.php(169): OC\Server->OC\{closure}()
#15 /var/www/html/3rdparty/pimple/pimple/src/Pimple/Container.php(122): OC\AppFramework\Utility\SimpleContainer->OC\AppFramework\Utility\{closure}()
#16 /var/www/html/lib/private/AppFramework/Utility/SimpleContainer.php(136): Pimple\Container->offsetGet()
#17 /var/www/html/lib/private/ServerContainer.php(154): OC\AppFramework\Utility\SimpleContainer->query()
#18 /var/www/html/lib/private/AppFramework/Utility/SimpleContainer.php(45): OC\ServerContainer->query()
#19 /var/www/html/lib/private/Server.php(1277): OC\AppFramework\Utility\SimpleContainer->get()
#20 /var/www/html/lib/base.php(635): OC\Server->boot()
#21 /var/www/html/lib/base.php(1224): OC::init()
#22 /var/www/html/console.php(31): require_once('...')
#23 /var/www/html/occ(33): require_once('...')

Config value bruteforcesettings/enabled refers to values from oc_appconfig table

MariaDB [nextcloud]> select * from oc_appconfig where configkey='enabled';
+-------------------------+-----------+-------------+------+------+
| appid                   | configkey | configvalue | type | lazy |
+-------------------------+-----------+-------------+------+------+
| ********                | enabled   | yes         |    2 |    0 |
| ***********             | enabled   | yes         |    2 |    0 |
| *******                 | enabled   | yes         |    2 |    0 |
| *********               | enabled   | no          |    2 |    0 |
| bruteforcesettings      | enabled   | 1           |   32 |    0 |
| ********                | enabled   | yes         |    2 |    0 |
| *******                 | enabled   | yes         |    2 |    0 |

On a fresh NextCloud install, bruteforcesettings configvalue is yes and type is 2. Let's change them:

MariaDB [nextcloud]> update oc_appconfig set configvalue='yes', type=2 where appid='bruteforcesettings' and configkey='enabled' limit 1;
Query OK, 1 row affected (0.002 sec)
Rows matched: 1  Changed: 1  Warnings: 0