I asked his opinion is all. I dont care to learn how to build a ported box, i personally think they dont sound good at all. But i have heard a LOT of sealed boxes that are insanely loud.
its because people in the past dont have actual ported box building knowledge based on cabin gain, ts parameters modeled on an enclosure software and RTA testing which resulted in sh*t bandwidth, peaky response and horrible group delay (accuracy) Again the setups of the 90s arent as loud as you think they are when compared to today's standards. Back then they used audio control meters which are literally at least 5 dbs less than now on a term lab meter and back then 150s was considered big dawgs. Now with stricter Term Lab Magnums, you really have to be "LOUD" LOUD, a 150 nowadays will absolute destroy 150s in the 90s at a lower bass frequency as well, people are doing 150s in the 15-25hz zone. The standard nowadays is 160 db for the loud people club and no sealed setup can ever hope to join unless its a 4th order. Not to mention i heard you mention scores with the window down, thats technically outlaw and our outlaw numbers are generally 5 db louder as well. Usually we measure strict with windows up meter on the dash in order for it to count as a real score so most 90s spl vehicles will fall flat on their face.
On the SQ side of things, you can do in car frequency response tests for transfer function and cabin gain then tune your enclosure low enough to balance out the cabin gain and get maximum usuable bandwidth which is a lot more than sealed which is completely left at the mercy of cabin gain which is not really SQ at all in most cases because your 50hz is 5-15 db stronger than your 28hz mean while with a properly designed ported, 6th order or 1/4 wave transmission line, you can achieve a 1-2 db variance between 20hz to 50hz out the box and with some RTA and DSP tuning with parametric EQs (which the 90s rarely had) you can get less than 1 db variance. With time alignment and beefier midbasses with lots of mids and highs power for cheap, you can get a perfect blend between midbass and subs for actual SQ portion. With subwoofer modeling software, you can also predict group delay (how fast, accurate and tight the sub will perform).
Our standards for sound quality is also far beyond what the 90s comprehension of sound can think of. We have both the proper installation methods of the 90s plus extreme amounts of power and headroom, electricals and the biggest game changer, digital signal processors (DSPs) usually with 8 to 10 channels of rca outputs for 3 way active front stages with mids midbass and midrange all fully bandpass crossover capable at any frequency 20hz to 20khz from -6 db slope to -24 db slopes with bessel, link witz riley or butterworth types of crossovers. Time alignment for perfect sound stage and individual left and right 31 band parametric EQ. Thats why they have a no dsp class for people in the 90s to compete because they have zero chance against DSPs.
People in the 90s lacked the tools, knowledge and technology to achieve the results we are capable of today. I'd recommend you checking out a MECA SQ/SPL or DB drag organizations and see what the game is like nowadays. Sorry for the chunk of text but you look like you needed some severe catching up with the times sir. Hope this helps clear some stuff up.