I have the same problem, i seems a bug in the last version of babel.
i fixed following this comment workaround
- delete node_modules and package-lock.json
- add “resolutions”: { “@babel/preset-env”: “^7.8.7” }, to package.json
- npm install npm-force-resolutions --save-dev
- npm install
- npx npm-force-resolutions
- npm install again
- then run your app(ionic cordova run android in my case)