How does the fallback-locale suppose to work with blocks field?

I struggle to work with fallback locale functionality and REST API. From what I observed so far, it does not work as I would expect and I don't know what am I doing wrong.
My collection has the blocks field defiintion as follows:

{
  type:'blocks',
  name: 'blocks',
  label: 'Bloki z treścią',
  localized: true,
  blocks: [
    Richtext,
    Columns,
    GalleryColumns,
    LargePhoto,
  ]
},

• It does not work for common queries like ?where[slug][equals]=slug-string?locale=en&fallback-locale=pl it only works when I query with /api/model/[itemId]?locale=en&fallback-locale=pl, and with /api/model?locale=en&fallback-locale=pl but this is something I can actually understand why, even if it does create a headache.
• It does not seem to work for blocks field, even if the one is localized: true and filled with data on locale which supposed to be the fallback one. The fields inside blocks are not localized: true as I figured that - logically - if the wrapping element (blocks field) is localized, that inner elements shouldn't be. It works on the UI - switching locale on admin to empty one, provides me with the blank blocks field, ready to be filled. However, i thought that leaving it as blank, should fill the content from the fallback on API request?

Current packeges version of mine:

  "dependencies": {
    "@payloadcms/plugin-seo": "^1.0.9",
    "dotenv": "^16.0.3",
    "express": "^4.18.2",
    "nodemailer": "^6.8.0",
    "nodemailer-sendgrid": "^1.0.3",
    "payload": "^1.2.0",
    "payload-s3-upload": "^1.1.2"
  },
  "devDependencies": {
    "nodemon": "^2.0.20"
  }

and config has localization provided as:

localization: {
    locales: [
      'pl',
      'en'
    ],
    defaultLocale: 'pl',
    fallback: true,
  },

How can I force this mechanism to return blocks field with data from fallback locale?