I have been going to gigs both large and small since the 1980’s, most metal ranging from Michael Schenker to Venom and lots in between. Here are a couple of observations.
Over the past five or so years I think the volume of gigs in the medium and large venues (Kentish Town up to Wembley arena) has reduced quite a bit. I believe this is due to Elf and Safety and the daily noise dose limited that came in around 2015 and slowly peculated through to various industries. My phone dB meter seemed to back this up with the average noise level being around 90-92dB which gives you your daily dose in around 2.5hrs. This has the consequence of actually increasing sound quality.
A recenish gig highlighted the skill of the engineer. I saw Tesseract supported by Betwen the Buried and Me and Plini at Shepherds Bush Empire. Plini sounded OK, but BTBAM sounded awful, distorted, low volume vocals and way too much drums and half an hour later Tesseract was like listening to the CD. Same venue, same sound system but different engineers. I rate Shepherds Bush as one of the best sounding venues, possibly due to its heritage as a BBC OB venue. I was also Impressed last time I went to Hammersmith Odeon (sorry I refuse to call it the Eventim Apollo!) to see Opeth, sounded like they had a recent overhaul of the sound system and it was very good.
Conversely, Brighton centre is always awful, sounds like a school sports hall and Wembley Arena always takes two or three songs for the engineers to get right probably due to doing the sound check empty and the people in the room having a larger effect that less resonant venues.
And as said small venues are real hit a miss affair, some great, some too loud and some just poor.
Anyway, keep going to see live music and buying the merch supports the artists more than streaming the songs in your front room.