We have Sitecore Hotfix 379282 installed in our 9.3 Sitecore environment (it has two nuget packages, Sitecore.Client.Hotfix.379282 and Sitecore.ContentSearch.Hotfix.379282). We're in the process of updating to Sitecore 10.1.1 right now.
Have the fixes introduced by this hotfix been resolved in any versions of Sitecore between 9.3 and 10.1.1?
Yes
If you open the \sitecore\shell\hotfixes\SC Hotfix 379282-1 CMS.Core 14.0.0 ContentSearch 6.0.0 Speak 6.0.0.txt file and view its contents, you can see the IDs of all of the bugs and other work items that are included in the hotfix:
Bug 361332: In certain cases the ContentSearch.Indexing.DisableDatabaseCaches setting disables caches for read operations
Bug 223702: SC_TICKET entries are never cleared from Properties table
Bug 235313: Index is always optimized after a rebuild ignoring the ContentSearch.Solr.OptimizeOnRebuild.Enabled setting
Bug 214239: Exception is thrown when Grid SPEAK 2.0 control is used
Bug 257381: Inconsistency in Validation Results dialog width
Bug 155383: Incorrect item data can be indexed if 'DisableDatabaseCaches' is set to 'true'
Bug 104112: Item tree copy does not reset workflow for descendants
Bug 360037: Select the Associated Content dialog: tree is not expanded to current selection when click "Browse"
Bug 250256: The ShowConfigLayers.aspx page doesn't consider the search parameter
Bug 118985: Heartbeat.aspx logs connection string password
Bug 332061: The only implementation of UserLockProvider is extremely inefficient
Product Backlog Item 257467: Rework TemplateEngine.GetTemplate API to avoid sequential execution
Product Backlog Item 185029: Use concurrent collection in DefaultLanguageFallbackStrategy to avoid blocking in multi-threading
Bug 119290: Incorrect standard values cache for inherited template
Then, you can search the release notes for the Sitecore releases at https://dev.sitecore.net/downloads to see if those numbers are listed as being implemented in that release. In this case, they were all fixed in version 10.0.0: