I have a VDSL connection with 22 down and 1 up. Without any limitation to the speeds, ping goes as much as 1500ms. With limitation to ~20M down and 0.9M up it usually stays under 200ms.

I now have a mikrotik hAP Lite and decided to try SFQ and fq_codel with the beta software. After setting them up and limiting the speeds, I see no difference in PING fluctuation. It keeps spiking as high as 200 when I'm pinging 1.1.1.1 (it's 10-20 when idle). Testing in websites like dslreports is even worse by spiking as high as 300-500ms.

Do I need to do any settings to my ISP's modem as well? Right now I use it for VOIP, so I can't just set it to bridge mode because I lose that function.
Modem stats are quite good I would say for stability. It has just 513 CRC for 11 days, and that 500 were In the first day for some reason. So it's less than 20 for 10 days.

For SFQ I used this: https://www.youtube.com/watch?v=phKi_NGJfpg
For fq_codel I used this: https://www.youtube.com/watch?v=wNT3CqmVFi4
The only difference I did from the videos is setting target to 192.168.88.0/24

Thanks

You need to set the target to whatever your WAN interface is (usually ether1 or vlan999 in my case as ISP requires VLAN tagging to get IP from them) instead of 192.168.88.0/24. Doing that will actually limit your LAN speed which is a bad practice.

After you set your target to eth1 the speeds will be inverted so your max DL on the GUI is actually your UL and viceversa for UL.

Also edit bucket size for both UL and DL to 0.01 or 0.005 to make the shaper more aggressive and thus reduce ping spikes.

If that doesn't helps too much try reducing a bit more your speeds till you hit a sweet spot between raw speed and latency.

As already noted, you need to correctly assign limits to the traffic to and from your router. To control traffic congestion, those limits must be 5%-20% lower than what is allocated by your ISP because there's no free lunch for QoS: traffic is controlled by either dropping packets over a hard limit or delaying them in a buffer with a scheduler. This is true for both you and your ISP. Buffering adds latency (CoDel is a packet scheduler) and if used dynamically by your ISP for congestion control, you might be out of luck no matter what you do on your little router.

As you know, CoDel is in development on Mikrotik and as such, it's not something I would use for buffer bloat at the moment if I had issues. A simple queue using SFQ should control solvable buffer issues with the caveat previously mentioned. Using a DSCP based strategy might perform better to optimize your VOIP traffic however.