The last time Bikini Kill played in London was in a room that now serves as the restaurant of a pub in Kentish Town. What a change 26 years can bring: on their return to the city last week, they filled the 5,000-capacity O2 Academy, Brixton, for two nights.

That changed status, in truth, is not the result of the timelessness of their music — scrappy punk rock that at its most tuneful was pleasingly familiar and at its least tuneful approximated the sound of fingernails scraping down a blackboard at extreme volume. So why had 10,000 people bought tickets to see them in London?

Some of them, doubtless, actually loved the music and nothing else — there’s always been an audience for loud shoutiness — but it’s likely that more of them also loved what Bikini Kill represent, and what they achieved. The group was one of the leading lights of the early 1990s riot grrrl movement, insisting on parity for women in a scene —indie rock — that liked to think of itself as a model of tolerance without always living up to its ideals. ‘Revolution Girl Style Now!’ Bikini Kill demanded.

Hence an audience that was overwhelmingly female (search ‘Bikini Kill’ on Twitter to see how much these shows meant to those women), and singer Kathleen Hanna — a startlingly charismatic presence — punctuating the bursts of noise with monologues about not rejecting prior waves of feminism, her own female rock heroes, and the sleaziness of a 42-year-old man hitting on her when she was 17. Some things have changed, though. When someone near the front shouted an old Bikini Kill slogan at the stage — ‘Girls to the front!’, an insistence that women should be able to enjoy punk shows without being barrelled around by slamdancing men — Hanna responded not with agreement, but with a statement of a new political orthodoxy: ‘Honestly, I can’t tell what someone’s gender identity is when I’m standing on a stage.’

For all their tunelessness, Bikini Kill had far-reaching effects in securing space for women in rock to be appreciated on their own terms. Right now, scores of the more interesting musicians in alternative music are women: St Vincent, Nilufer Yanya, Courtney Barnett, Mitski, U.S. Girls, Anna Calvi and more. Not so long ago, they would have been packaged off by the music industry into a corner marked ‘female singer-songwriters’ (Q magazine even had a word for them: ‘warbelstresses’).

A case in point is Cate Le Bon, whose fifth solo album, Reward, is one of the year’s best. You wouldn’t call her a communicator — she barely spoke during her show at the Village Underground, and her lyrics are so elliptical as to be baffling. But her musical world is enveloping and gorgeous: lush songs coloured with saxophone and marimba, disrupted by brief, expressive flurries of guitar from Le Bon. They seemed both familiar and awry, like a TV picture with the colour and contrast turned up too high. It sometimes felt as though the separate elements of the songs should be falling apart, but they were held together by Le Bon’s crystalline soprano.

At times she did a great deal with very little: the set closed with ‘What’s Not Mine’, from her first album, which was a handful of hammered chords with almost no ornamentation. It was a little like the Velvet Underground reimagined for a pootle through the Welsh countryside, both gleefully eccentric and furiously compelling. It ended with Le Bon standing on the low drum riser, soloing away as her bandmates left the stage. It was almost the only moment of ego in the set, and it was thoroughly deserved.

Bikini Kill, O2 Academy, Brixton