Yep, the code you provided is compiled into this:

command_0="$(cat file.txt | grep "READY")"
__status=$?
if [ "${__status}" != 0 ]; then
    echo "Failed to read the file"
fi

So, the outcome would depend on the pipefail option. (set -o pipefail)

As you suggested, an Amberic snippet would be:

import { file_read } from "std/fs"
import { match_regex } from "std/text"

const result = file_read("file.txt") failed {
    echo "Failed to read the file"
}
if match_regex(result, "READY"):
    echo "file.txt contains READY"