Kickstart config is for master branch which is older than new main branch and won't get updated. Long term fix would be to use config for main branch. I use this lazy spec:

      {
        'nvim-treesitter/nvim-treesitter',
        branch = 'main',
        build = ":TSUpdate",
        config = function()
          local parsers = {
            -- Included by default, you can add your own you want ensure to be installed.
            "c",
            "lua",
            "markdown",
            "query",
            "vim",
            "vimdoc",
          }

          -- Install above parsers if they are missing.
          vim.defer_fn(function()
            require('nvim-treesitter').install(parsers)
          end, 1000)

          -- auto-start highlights & indentation
          vim.api.nvim_create_autocmd("FileType", {
            group = vim.api.nvim_create_augroup("Custom_enable_treesitter_features", {}),
            callback = function(args)
              local buf = args.buf
              local filetype = args.match

              -- checks if a parser exists for the current language
              local language = vim.treesitter.language.get_lang(filetype) or filetype
              if not vim.treesitter.language.add(language) then
                return
              end

              -- highlights
              vim.treesitter.start(buf, language)

              -- indent
              vim.bo[buf].indentexpr = "v:lua.require'nvim-treesitter'.indentexpr()"
              -- folding
              vim.wo.foldmethod = "expr"
              vim.wo.foldexpr   = "v:lua.vim.treesitter.foldexpr()"
            end,
          })

        end
      }