Cannot mount USB External HD with ext3, possible hardware failure

I'm a Software Engineer with limited SysEng experience. I have a few weeks old "WD 4 TB Elements Portable External Hard Drive", that is a USB 4 TB External HD. I've installed it on Raspberry PI, and created a unique ext3 partition. The HD was almost full when last night when, during an rsycn, it stopped working. I tried a quick reboot, after which I could not mount it. The drive, when on, makes a non encouraging "clank" noise periodically. This is the error when mounting:

ubuntu@ubuntu:~$ sudo mount /dev/sdb1 /mnt/nfts/
mount: /mnt/nfts: wrong fs type, bad option, bad superblock on /dev/sdb1, missing codepage or helper program, or other error.

I've googled a bit and here below some commands I've run against the drive: From dmesg

[  147.507499] sd 1:0:0:0: [sdb] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[  147.507519] sd 1:0:0:0: [sdb] tag#0 Sense Key : Aborted Command [current]
[  147.507533] sd 1:0:0:0: [sdb] tag#0 Add. Sense: No additional sense information
[  147.507550] sd 1:0:0:0: [sdb] tag#0 CDB: Read(16) 88 00 00 00 00 00 00 00 00 00 00 00 00 08 00 00
[  147.507567] blk_update_request: I/O error, dev sdb, sector 0 op 0x0:(READ) flags 0x80700 phys_seg 1 prio class 0

More from dmesg

[  278.832149] Buffer I/O error on dev sdb1, logical block 0, lost sync page write
[  278.839728] EXT4-fs (sdb1): I/O error while writing superblock
[  278.845737] EXT4-fs (sdb1): no journal found`

From tune2fs

ubuntu@ubuntu:~$ sudo tune2fs -l /dev/sdb1
tune2fs 1.45.5 (07-Jan-2020)
Filesystem volume name:   
Last mounted on:          /mnt/nfts
Filesystem UUID:          e4e0f609-7beb-4610-bb43-6a807f4f88b5
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery sparse_super large_file
Filesystem flags:         unsigned_directory_hash
Default mount options:    user_xattr acl
Filesystem state:         clean with errors
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              244187136
Block count:              976745728
Reserved block count:     48837286
Free blocks:              116576385
Free inodes:              242495519
First block:              0
Block size:               4096
Fragment size:            4096
Reserved GDT blocks:      791
Blocks per group:         32768
Fragments per group:      32768
Inodes per group:         8192
Inode blocks per group:   512
Filesystem created:       Wed Jan 12 13:25:22 2022
Last mount time:          Wed Feb 23 13:56:10 2022
Last write time:          Wed Feb 23 14:07:39 2022
Mount count:              8
Maximum mount count:      -1
Last checked:             Wed Jan 12 13:25:22 2022
Check interval:           0 ()
Lifetime writes:          2976 GB
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:	          256
Required extra isize:     32
Desired extra isize:      32
Journal inode:            8
Default directory hash:   half_md4
Directory Hash Seed:      13549940-8c27-4c2a-87e2-e3f23ba4daa3
Journal backup:           inode blocks
FS Error count:           279
First error time:         Sun Jan 16 11:37:40 2022
First error function:     ext4_mb_generate_buddy
First error line #:       744
First error inode #:      0
First error block #:      0
Last error time:          Wed Feb 23 14:07:39 2022
Last error function:      ext4_mb_generate_buddy
Last error line #:        744
Last error inode #:       0
Last error block #:       0

I tried fsck but I got no significant output after one night, so stopped and rebooted. The HD is obviosly experiencing an hardware failure and I guess there are ton of bad sectors. Luckily the content of the HD are thousands of small files, and my hope is to recover as many of them as possible. Can someone point me in the right direction? What can I do to investigate the issue further and try to restore access to whatever is still stored on healthy sectors? Thanks in advance. Giovanni