As mentioned many, many times before in other posts.... your console's ability to read pressed Playstation 2 games doesn't show that it's laser is in A-grade condition.
Getting older PS2s to read recordable discs puts a greater strain on the laser, and weak lasers might be unable to even read burned discs.
If you didn't use Verbatim DVD-R discs that were manufactured by either Mitsubushi or Taiyo Yuden, your PS2 might either wear out it's laser quicker or it won't even read those discs.
Unmodified SCPH-77006 with SM 3.6
SCPH-39006 with M-chip modchip, SCPH-10281 NA and refurb Seagate 80GB HDD
SCPH-10000 v1.00 with SCPH-10190 PCMCIA NA and SCPH-20400 HDD unit